Stoichiometry. Can You Make 2.00 Grams of a Compound?

Size: px
Start display at page:

Download "Stoichiometry. Can You Make 2.00 Grams of a Compound?"

Transcription

1 Introduction Stoichiometry... Can You Make 2.00 Grams of a Compound? Catalog No. AP4554 Publication No Use your skills of predicting chemical reactions, balancing equations, and calculating molar mass to solve a complex stoichiometry problem. Then test your laboratory techniques by mixing the reactants and isolating exactly 2.00 g of a compound. Concepts Balancing equations Stoichiometry Molar mass Solubility rules Background Stoichiometry is the branch of chemistry that deals with the numerical relationships and mathematical proportions of reactants and products in chemical reactions. For any chemical equation the mole, mass, and atom ratios must remain constant. The coefficients from a balanced chemical equation provide definite ratios between the number of moles of reactants and products involved (equation 1). Equation 1: N 2 (g) + 3H 2 (g) 2N (g) ne mole of any chemical substance contains particles (molecules, atoms, etc.) and has a mass equal to the sum of atomic weights of all elements in the formula. Therefore, the mole ratio of a balanced chemical equation can be converted into a mass ratio or number of particles ratio. These ratios can be used as conversion factors to determine the exact amounts of reactants that combine and products that form during a chemical change (equation 2). Equation 2: Balanced equation: N 2 (g) + 3H 2 (g) 2N (g) Molar mass: Mass: 28.0 g g = 34.0 g When two ionic compounds are placed in solution, a double replacement reaction can occur. Double replacement reactions are also called double displacement or exchange reactions and follow the pattern: A + X + B + Y B + X + A + Y. Normally, the reactants are chosen so one product will precipitate out of solution while the other ions stay in solution. In this way, one of the products can be easily isolated by filtration. Equation 3 is an example of a double replacement reaction. Equation 3: Pb(N 3 (aq) + KI(aq) PbI 2 (s) + KN 3 (aq) When the reacting ionic compounds are dissolved in water, they separate into the four different ions that are free to move around and then re-combine to form the new products. If one of the combination of ions is insoluble in water, it will precipitate out of solution. In equation 3, lead iodide (PbI 2 ) precipitates out of solution. Some ionic solids also contain water molecules that are trapped within their crystal structure. These are called hydrated compounds. An example of a hydrated compound would be copper(ii) sulfate pentahydrate, Cu(S 4 ) 5H 2. During the dissolving process, the water molecules are released into the solution. In order to produce the 2.00 grams of desired product in the laboratory using a double replacement reaction, a balanced equation is required and the product that will precipitate must be identified. The next step is to determine the molar mass of each reactant and product, and finally use dimensional analysis to determine the quantities of reactants required. The following four steps describe the process in detail. CHEM-FAX...makes science teaching easier. IN

2 Step 1. Write a balanced formula equation for the reaction. Preparing a balanced chemical formula equation is the first step in understanding a reaction. Start the process by determining what reaction is occurring and write out the names of all reactants and products. Equation 4: Reaction: nitrogen + hydrogen = ammonia Next, prepare an unbalanced equation by writing out the chemical formula for each reactant and product. Equation 5: Unbalanced equation: N 2 + H 2 N Finally, the chemical equation must be balanced. The key principle in balancing equations is that atoms are conserved in a chemical reaction. Therefore, the same number and type of atoms must be found among the reactants and products of a reaction. For example, if you start with two nitrogen atoms in the reactants, you must have two nitrogen atoms in the products. Equation 6: Balanced equation: N 2 + 3H 2 2N Most chemical equations can be balanced by trial and error. This is done by adding up the quantity of each atom present on the reactants side of the equation and on the product side of the equation. Identify which atoms are not balanced and determine what coefficients are necessary in front of one of the reactants or products to balance the quantity of that atom on both sides of the equation. Step 2. Predict which compound will form a precipitate using general solubility rules. When working with aqueous solutions, it is helpful to understand a few rules concerning which substances are soluble in water and which will form precipitates. The more common solubility rules are listed below: 1. All common salts of the Group IA (Li, Na, K, etc.) elements and the ammonium ion are soluble. 2. All common acetates and nitrates are soluble. 3. All binary (two element) compounds of Group VIIA elements (other than F) with metals are soluble, except those of silver, mercury(i), and lead. 4. All sulfates are soluble except those of barium, strontium, lead, calcium, silver, and mercury(i). 5. Except for those in Rule #1, carbonates, hydroxides, oxides, and phosphates are insoluble. Using these solubility rules, predict if any of the possible combination of reactant ions can form insoluble compounds. If so, the product will precipitate out of solution. Step 3. Calculate the mass of reactants needed to produce the 2.00 g of precipitate. To calculate the mass of reactants needed to produce 2.00 g of a precipitated product requires the determination of the molar mass of each reactant and product. Molar mass (also called molecular weight) is the mass in grams of one mole of a substance. Molar mass is determined by adding the atomic masses of all of the atoms in the chemical formula. For example, the chemical formula CuS 4 5H 2 shows that in 1 mole of this compound, there are 1 mole of Cu ions, 1 mole of S 4 ions, and 5 moles of H 2 which gives a total of 1 mole of Cu, 1 mole of S, 10 moles of H and 9 moles of atoms. The total mass of each element in the compound is equal to the number of moles of atoms of the element multiplied by its atomic mass. The molar mass of copper(ii) sulfate pentahydrate is equal to the sum of the total masses of each element: number of moles of atoms atomic mass = total mass of element 1 mole of Cu g Cu/mole = g Cu 1 mole of S g S/mole = g S 9 moles of g /mole = g 10 moles of H 1.01 g H/mole = g H Molar Mass of CuS 4 5H g

3 nce the molar mass of each reactant and product is determined, the next step is to determine the number moles in 2.00 g of precipitate using equation 5. Equation 5: moles = grams/molar mass For example, if 2.00 g of copper(ii) sulfate pentahydrate is desired, the number of moles will be: 2.00 g g/mol or moles. Using dimensional analysis, the equations would be: 200 g mole g = mole Lastly, use the coefficients in the balanced equation to determine the number of moles of each of the reactants required to produce the desired number of moles of precipitate. nce the number of moles is obtained, use the following equation to calculate the number of grams of each reactant. Equation 6: grams = moles molar mass Step 4. Use the calculated masses of reactants to make and recover the 2.00 grams of precipitate. After the chemical equation is balanced, the precipitated product is determined and the mass of each reactant required to produce 2.00 g of product is calculated, the reaction can be performed in lab. Both of the reactants need to be dissolved in separate beakers using 25 ml of distilled water for each reactant. Then the two solutions need to be mixed together to form the precipitate. The precipitate will be recovered by filtration using a pre-massed piece of filter paper. The precipitate will be dried under a heat lamp or in a drying oven, and then the mass of the solid determined. The precipitate will be turned in to your teacher and the percent error calculated for the experiment. Student Tips When writing chemical formulas for the reactants and products, remember that the sum of all of the positive and negative charges in the compound must equal zero. Use subscripts to indicate the number of ions needed to equalize the charges. Parentheses are required to enclose polyatomic ions when there is more than one in the formula, such as the two nitrate ions in Ba(N 3. After the formulas for individual compounds are correctly written, only the coefficients can be changed to balance the equation and to obtain the same number of atoms of each element in both the reactants and products. Before measuring out the reactants, do the calculated mass values seem reasonable? According to the Law of Conser vation of Mass, the total mass of all reactants must equal the total mass of all products. Not all solids precipitate out of solution immediately. Some precipitates, such as calcium sulfate, require more than an hour to fully precipitate out of solution. Patience is required. Safety Information The compounds selected for this experiment have low to moderate toxicity, but avoid breathing the dust or getting any in yours eyes or on your skin. Zinc sulfate is a skin and mucous membrane irritant and is mildly toxic. Sodium carbonate and potassium carbonate may be skin irritants. Magnesium sulfate irritates eyes and the respiratory tract. Calcium chloride is moderately toxic. All solutions may be flushed down the drain and solids may be thrown in the trash. Wear chemical splash goggles, chemicalresistant gloves, and chemical-resistant aprons.

4 Background Teacher Notes Stoichiometry... Can You Make 2.00 Grams of a Compound? This experiment is designed to be a culminating activity to provide the teacher with feedback on how well students have mastered several fundamental skills in chemistry. It is assumed that the students already have an understanding of the concepts of formula writing, balancing chemical equations, determining molar mass values, using dimensional analysis for problem solving, and applying stoichiometric relationships to determine experimental proportions. The students should also be proficient in basic lab techniques, such as filtration, the proper handling of chemicals and using mechanical or electronic balances to measure mass. Perhaps they may have already used solubility rules or charts to study precipitate reactions between ions in solution. In order to successfully complete this experiment, students will need to apply all of these skills and plan the steps of an experiment the way a chemist does in industry. Materials Included in Kit Additional Materials Needed for the Lab Calcium acetate monohydrate, Ca(C 2 2 H 2, 65 g Balance to measure to 0.01g Calcium chloride dihydrate, CaCl 2 2H 2, 60 g Filtration setup (see Figure 1a or 1b) Magnesium sulfate heptahydrate, Mg(S 4 7H 2, 100 g Heat lamp or drying oven Potassium carbonate, K 2 C 3, 60 g Filter paper, 1 per lab group Sodium carbonate, Na 2 C 3, 50 g Beakers, 100-mL, 2 per lab group Zinc Sulfate heptahydrate, ZnS 4 7H 2, 100 g Student and teacher instructions Figure 1a: How to Set Up a Gravity Filtration Place filter paper in funnel and wet slightly with distilled water. Figure 1b: How to Set Up a Vacuum Filtration Aspirator screws onto faucet. funnel support filter paper long stem pipet beaker (or flask) Pour solution slowly into funnel with the aid of a stirring rod. Using a wash bottle, wash any solid remaining in the beaker into the filter paper. Safety Precautions The six chemicals provided in this kit were selected because of their relatively low toxicity levels and ease of disposal. Zinc sulfate is a skin and mucous membrane irritant and mildly toxic. Sodium carbonate and potassium carbonate may be skin irritants. Magnesium sulfate irritates eyes and respiratory tract. Calcium chloride is moderately toxic. Please review all MSDS sheets before starting lab. Wear chemical splash goggles, chemical-resistant gloves, and chemical-resistant aprons. 8 The flow of water through the aspirator creates a partial vacuum in the flask.

5 Pre-Lab Teacher Tips The pre-lab is essentially a dry lab and should highlight any deficiencies or problem areas before a student attempts to actually isolate 2.00 g of product. Typical mistakes made by the students include incorrectly written chemical formulas, errors in balancing the equations, wrong molar mass calculations or mistakes in the dimensional analysis using the stoichiometric conversion factors. Ideally, the pre-lab should be corrected and handed back to the students before they begin the actual laboratory procedure. The pre-lab also makes an excellent guide for the experiment. Results for Pre-Lab Calculations Sample Problem: How would you prepare 2.00 grams of precipitate by reacting barium chloride dihydrate with silver nitrate? Directions: Complete the following equations/problems showing ALL WRK, including the necessary units and labels. 1. Write a complete word equation listing the names of the reactants and the predicted products. A: B: C: D: barium chloride dihydrate + silver nitrate silver chloride + barium nitrate + H 2 2. Write a balanced formula equation for your double displacement reaction. Predict which compound will form a precipitate and indicate this in the equation using the symbol, (s), following the chemical formula. A: B: C: D: BaCl 2 2H 2 + 2AgN 3 2AgCl(s) + Ba(N H 2 3. Calculate the molar mass of each reactant and product and put the answers in the blank spaces below. A: B: C: D: H molar mass reactant A: molar mass reactant B: molar mass product C: molar mass product D: Work Space 1 ( g Ba/mol) = g/mol 2 (35.45 g Cl/mol) = g/mol 4 (1.01 g H/mol) = 4.04 g/mol 2 (16.00 g /mol) = g/mol 1 ( g Ag/mol) = g/mol 1 (14.01 g N/mol) = g/mol 3 (16.00 g /mol) = g/mol 1 ( g Ag/mol) = g/mol 1 (35.45 g Cl/mol) = g/mol 1 ( g Ba/mol) = g/mol 2 (14.01 g N/mol) = g/mol 6 (16.00 g /mol) = g/mol molar mass H 2 : 2 (1.01 g H/mol) = 2.02 g/mol 1 (16.00 g /mol) = g/mol 9

6 4. Calculate the number of moles in 2.00 g of the precipitated product. Molar mass of precipitate: # of moles of precipitate: Use dimensional analysis to determine the mass of each reactant required to make 2.00 grams of your precipitate. First, determine the number of moles of each reactant and product and then calculate the mass of all reactants and product(s). Put the answers in the blank spaces below. Does the total mass of all reactants equal the total mass of all products? If not, check your work. Moles: A: B: C: D: H Grams: A: B: C: D: H mass of reactant A needed: mass of reactant B needed: mass of product C that should form: mass of product D that should form: mass of H 2 that should form: Work Space mole g/mol = 1.71 g mole g/mol = 2.38 g mole g/mole = 2.01 g mole g/mol = 1.83 g mol g/mol = g 6. Complete the data chart below to determine the mass of precipitate formed in the sample experiment: Mass of dry filter paper + precipitate 2.97 g Mass of dry filter paper 1.02 g = Mass of precipitate 1.95 g 7. Calculate your percent error based on the relationship below: % error = 1.95 g 2.00 g 100 = 2.5% 2.00 g 10

7 Teacher Tips for Experiment This laboratory procedure is an open-ended lab and not a cookbook lab. Therefore, the students must develop a detailed procedure and the laboratory portion of this activity should not be started until all chemical formula equations, calculations, and procedures have been checked by the teacher. Any mistakes can be corrected at this point or you can simply let them find the error of their ways for themselves. There are enough chemicals included in this kit for five sets of experiments. There are 12 different combinations that will produce a precipitate reaction, so each lab group has a unique problem to solve. Cut out the possible pairs of reactants found on page 13 and assign them to lab groups. Experimental errors can result if the students do not dissolve the reactants completely in distilled water before mixing. Some of the solid filtered out may be the undissolved reactant(s). Tap water should not be used because the impurities in it, such as calcium and magnesium ions in hard water, can also precipitate out and interfere with the desired reaction. The filter paper and precipitate must be completely dried and any water of hydration must be removed by the drying process. Usually, the most accurate method to ensure complete dehydration is by heating until a constant mass is achieved. Most results fall within a 5 10% error range. For any group that produces CaS 4 (s), a 1.7% error is caused by the very slight solubility of this precipitate (0.033 g CaS 4 dissolves in 50 ml of the original solution). It is not unusual for some groups to obtain less than a 5% error through careful measurements and techniques. A few groups may obtain greater than a 25% error, which can usually be traced to an incorrect formula or calculation resulting in the wrong mass of the starting reactant(s). Some of the solids, such as calcium sulfate, do not immediately precipitate out of solution. Patience and additional time are required. Disposal All solids can be buried in a landfill site approved for the disposal of chemical and hazardous wastes, following the Flinn Disposal Method #26a. Solutions can be simply poured down the drain if your school is connected to a sanitary sewer system with a water treatment plant according to Flinn Disposal Method #26b. Acknowledgments Special thanks to Mark A. Case from Emmaus High School, Emmaus, PA for developing this laboratory procedure. Materials for Stoichiometry... Can You Make 2.00 g of a Compound? Kit are available from Flinn Scientific, Inc. Catalog No. AP4554 AP1055 AP1284 Description Stoichiometry... Can You Make 2.00 Grams of a Compound? Kit Laboratory oven Büchner Funnel, Porcelain, 100-mm AP1521 Stopper for Büchner funnel, no. 6 GP4072 Filtering Flask, 250-mL Consult your Flinn Scientific Catalog/Reference Manual for current prices. 11

8 Possible Pairs of Reactants Directions: Use a scissors to cut apart the possible pairs of assigned reactants. Have each lab group draw a card to determine which pair they will use for their experiment. #1 #2 A. zinc sulfate heptahydrate A. zinc sulfate heptahydrate B. calcium acetate monohydrate B. sodium carbonate #3 #4 A. zinc sulfate heptahydrate A. zinc sulfate heptahydrate B. calcium chloride dihydrate B. potassium carbonate #5 #6 A. magnesium sulfate heptahydrate A. magnesium sulfate heptahydrate B. calcium acetate monohydrate B. sodium carbonate #7 #8 A. magnesium sulfate heptahydrate A. magnesium sulfate heptahydrate B. calcium chloride dihydrate B. potassium carbonate #9 #10 A. calcium acetate monohydrate A. calcium acetate monohydrate B. sodium carbonate B. potassium carbonate #11 #12 A. sodium carbonate A. calcium chloride dihydrate B. calcium chloride dihydrate B. potassium carbonate 12

9 Theoretical Results For each pair of reactants below there is a complete word equation, balanced formula equation, molar mass values and grams of reactants needed and products formed. Reactant Pair #1 zinc sulfate heptahydrate + calcium acetate monohydrate calcium sulfate + zinc acetate + water ZnS 4 + Ca(C 2 2 H 2 CaS 4 (s) + Zn(C H g/mole g/mole g/mole g/mole g/mole 4.22 g 2.59 g 2.00 g 2.70 g 2.12 g Reactant Pair #2 zinc sulfate heptahydrate + sodium carbonate zinc carbonate + sodium sulfate + water ZnS 4 + Na 2 C 3 ZnC 3 (s) + Na 2 S 4 + 7H g/mole g/mole g/mole g/mole g/mole 4.59 g 1.69 g 2.00 g 2.27 g 2.01 g Reactant Pair #3 zinc sulfate heptahydrate + calcium chloride dihydrate calcium sulfate + zinc chloride + water ZnS 4 + CaCl 2 2H 2 CaS 4 (s) + ZnCl 2 + 9H g/mole g/mole g/mole g/mole g/mole 4.22 g 2.16 g 2.00 g 2.00 g 2.38 g Reactant Pair #4 zinc sulfate heptahydrate + potassium carbonate zinc carbonate + potassium sulfate + water ZnS 4 + K 2 C 3 ZnC 3 (s) + K 2 S 4 + 7H g/mole g/mole g/mole g/mole g/mole 4.59 g 2.20 g 2.00 g 2.78 g 2.01 g Reactant Pair #5 magnesium sulfate heptahydrate + calcium acetate monohydrate calcium sulfate + magnesium acetate + water MgS 4 + Ca(C 2 2 H 2 CaS 4 (s) + Mg(C H g/mole g/mole g/mole g/mole g/mole 3.62 g 2.59 g 2.00 g 2.09 g 2.12 g Reactant Pair #6 magnesium sulfate heptahydrate + sodium carbonate magnesium carbonate + sodium sulfate + water MgS 4 + Na 2 C 3 MgC 3 (s) + Na 2 S 4 + 7H g/mole g/mole g/mole g/mole g/mole 5.85 g 2.51 g 2.00 g 3.37 g 2.99 g 13

10 Reactant Pair #7 magnesium sulfate heptahydrate + calcium chloride dihydrate calcium sulfate + magnesium chloride + water MgS 4 + CaCl 2 2H 2 CaS 4 (s) + MgCl 2 + 9H g/mole g/mole g/mole g/mole g/mole 3.62 g 2.16 g 2.00 g 1.41 g 2.38 g Reactant Pair #8 magnesium sulfate heptahydrate + potassium carbonate magnesium carbonate + potassium sulfate + water MgS 4 + K 2 C 3 MgC 3 (s) + K 2 S 4 + 7H g/mole g/mole 84.31g/mole g/mole g/mole 5.85 g 3.28 g 2.00 g 4.13 g 2.99 g Reactant Pair #9 calcium acetate monohydrate + sodium carbonate calcium carbonate + sodium acetate + water Ca(C 2 2 H 2 + Na 2 C 3 CaC 3 (s) + 2NaC H g/mole g/mole g/mole g/mole g/mole 3.52 g 2.12 g 2.00 g 3.28 g 0.36 g Reactant Pair #10 calcium acetate monohydrate + potassium carbonate calcium carbonate + potassium acetate + water Ca(C 2 2 H 2 + K 2 C 3 CaC 3 (s) + 2KC H g/mole g/mole g/mole g/mole g/mole 3.52 g 2.76 g 2.00 g 3.92 g 0.36 g Reactant Pair #11 sodium carbonate + calcium chloride dihydrate calcium carbonate + sodium chloride Na 2 C 3 + CaCl 2 2H 2 CaC 3 (s) + 2NaCl + 2H g/mole g/mole g/mole g/mole g/mole 2.12 g 2.94 g 2.00 g 2.34 g 0.72 Reactant Pair #12 calcium chloride + potassium carbonate calcium carbonate + potassium chloride CaCl 2 2H 2 + K 2 C 3 CaC 3 (s) + 2KCl + 2H g/mole g/mole g/mole g/mole g/mole 2.94 g 2.76 g 2.00 g 2.98 g 0.72 The steps used to determine the above values are the same as those described in the background section of the experiment. The total masses of reactants needed for a class with 12 lab groups to complete the experiment are g ZnS 4 ; g MgS 4 ; g Ca(C 2 2 H 2 ; 8.44 g Na 2 C 3 ; 10.2; and g K 2 C 3. There are enough chemicals included in this kit for five sets of experiments. They are also common laboratory chemicals that have applications in many other experiments. 14

A Chemical Reaction of Cobalt(II) Nitrate with Sodium Phosphate - A Lesson in Stoichiometry -

A Chemical Reaction of Cobalt(II) Nitrate with Sodium Phosphate - A Lesson in Stoichiometry - A Chemical Reaction of Cobalt(II) Nitrate with Sodium Phosphate - A Lesson in - From a balanced chemical equation we can deduce or calculate many things. For example, a balanced chemical equation can be

More information

CHM 130LL: Mole Relationships

CHM 130LL: Mole Relationships CHM 130LL: Mole Relationships Introduction Moles A mole, known as the chemist s dozen, relates the submicroscopic world of atoms and molecules to the much larger world of weighable amounts of chemicals.

More information

THREE CHEMICAL REACTIONS

THREE CHEMICAL REACTIONS THREE CHEMICAL REACTIONS 1 NOTE: You are required to view the podcast entitled Decanting and Suction Filtration before coming to lab this week. Go to http://podcast.montgomerycollege.edu/podcast.php?rcdid=172

More information

5. Determine the limiting reagent and calculate the theoretical yield of a reaction. 6. Calculate percent yield.

5. Determine the limiting reagent and calculate the theoretical yield of a reaction. 6. Calculate percent yield. Stoichiometry The term "stoichiometry" refers to the quantitative relationships between reactants and products in chemical reactions. In a balanced chemical equation, the coefficients (or mole ratios)

More information

General Chemistry Lab Experiment 4. Limiting Reactant

General Chemistry Lab Experiment 4. Limiting Reactant General Chemistry Lab Experiment 4 Limiting Reactant INTRODUCTION Two factors affect the yield of products in a chemical reaction: (1) the amounts of starting materials (reactants) and (2) the percent

More information

Molarity of Ions in Solution

Molarity of Ions in Solution APPENDIX A Molarity of Ions in Solution ften it is necessary to calculate not only the concentration (in molarity) of a compound in aqueous solution but also the concentration of each ion in aqueous solution.

More information

Chapter 10. Mole-Mole Stoichiometry. Example 10/21/2011. Chemistry Relationships in Chemical Reactions

Chapter 10. Mole-Mole Stoichiometry. Example 10/21/2011. Chemistry Relationships in Chemical Reactions 10/1/011 Chapter 10 Chemistry Relationships in Chemical Reactions Mole-Mole Stoichiometry When writing a balanced chemical equation, one can make relationships between any two substances in the reaction

More information

Stoichiometry: Mass-mass and percent yield in a precipitate reaction

Stoichiometry: Mass-mass and percent yield in a precipitate reaction Stoichiometry: Mass-mass and percent yield in a precipitate reaction Prelab Assignment: You will complete the Title, Purpose, Background information, Storyboard, and BLANK data table portion of your lab

More information

Chapter 6 Chemical reactions Classification And Mass Relationships. Chapter 6 1

Chapter 6 Chemical reactions Classification And Mass Relationships. Chapter 6 1 Chapter 6 Chemical reactions Classification And Mass Relationships Chapter 6 1 Chemical reactions and Chemical Equations Balancing Chemical Equations Mole, Avogadro s Number Stoichiometric Problems Percent

More information

Equations & Quantitative Relationships. + O 2(g)» H 2» 2 H 2

Equations & Quantitative Relationships. + O 2(g)» H 2» 2 H 2 Woods Chem-1 Lec-05 09-2 Stoichiometry (std)+ Page 1 States of matter: (s) (l) (g) (aq) Balancing Equations: Equations & Quantitative Relationships H 2 (g) + O 2(g)» H 2 Can t change H 2 O to H 2 O 2 2

More information

Solutions for Practice Problems. Section 9.1 Making Predictions About Solubility. Ions. Formula. PbCl 2. Pb 2+ Cl. Zn 2+ O 2. ZnO.

Solutions for Practice Problems. Section 9.1 Making Predictions About Solubility. Ions. Formula. PbCl 2. Pb 2+ Cl. Zn 2+ O 2. ZnO. Chapter 9 Aqueous Solutions Solutions for Practice Problems Section 9.1 Making Predictions About Solubility Student Textbook page 335 1. Problem Decide whether each of the following salts is or in distilled

More information

COPYRIGHT FOUNTAINHEAD PRESS

COPYRIGHT FOUNTAINHEAD PRESS Stoichiometry of Lead Iodide: A Mole Ratio Study Objectives: To investigate the stoichiometry of the potassium iodide lead nitrate system in water. The volumes of reagents will be varied, and the mass

More information

CHEMISTRY 102B Practice Hour Exam I. Dr. D. DeCoste T.A (30 pts.) 16 (15 pts.) 17 (15 pts.) Total (60 pts)

CHEMISTRY 102B Practice Hour Exam I. Dr. D. DeCoste T.A (30 pts.) 16 (15 pts.) 17 (15 pts.) Total (60 pts) CHEMISTRY 102B Practice Hour Exam I Spring 2016 Dr. D. DeCoste Name Signature T.A. This exam contains 17 questions on 5 numbered pages. Check now to make sure you have a complete exam. You have one hour

More information

Calculating Atoms, Ions, or Molecules Using Moles

Calculating Atoms, Ions, or Molecules Using Moles TEKS REVIEW 8B Calculating Atoms, Ions, or Molecules Using Moles TEKS 8B READINESS Use the mole concept to calculate the number of atoms, ions, or molecules in a sample TEKS_TXT of material. Vocabulary

More information

Determination of a Chemical Formula

Determination of a Chemical Formula 1 Determination of a Chemical Formula Introduction Molar Ratios Elements combine in fixed ratios to form compounds. For example, consider the compound TiCl 4 (titanium chloride). Each molecule of TiCl

More information

Teacher Notes and Answers

Teacher Notes and Answers SECTION 8.1 Describing Chemical Reactions Teacher Notes and Answers SECTION 1 Describing Chemical Reactions 1. The reactant is ammonium dichromate. The products are chromium(iii) oxide and water. 2. This

More information

Stoichiometry Limiting Reagent Laboratory. Chemistry 118 Laboratory University of Massachusetts, Boston

Stoichiometry Limiting Reagent Laboratory. Chemistry 118 Laboratory University of Massachusetts, Boston Chemistry 118 Laboratory University of Massachusetts, Boston STOICHIOMETRY - LIMITING REAGENT --------------------------------------------------------------------------------------------------------------------------------------------

More information

CHEMISTRY 102B Hour Exam I. Dr. D. DeCoste T.A (30 pts.) 16 (15 pts.) 17 (15 pts.) Total (60 pts)

CHEMISTRY 102B Hour Exam I. Dr. D. DeCoste T.A (30 pts.) 16 (15 pts.) 17 (15 pts.) Total (60 pts) CHEMISTRY 102B Hour Eam I February 17, 2015 Dr. D. DeCoste Name Signature T.A. This eam contains 17 questions on 6 numbered pages. Check now to make sure you have a complete eam. You have one hour and

More information

1. Hydrobromic acid reacts with aqueous lithium sulfide Molecular Equation

1. Hydrobromic acid reacts with aqueous lithium sulfide Molecular Equation NAME Hr Chapter 4 Aqueous Reactions and Solution Chemistry Practice B (Part 1 = Obj. 1-3) (Part 2 = Obj. 4-6) Objective 1: Electrolytes, Acids, and Bases a. Indicate whether each of the following is strong,

More information

The Reaction of Calcium Chloride with Carbonate Salts

The Reaction of Calcium Chloride with Carbonate Salts The Reaction of Calcium Chloride with Carbonate Salts PRE-LAB ASSIGNMENT: Reading: Chapter 3 & Chapter 4, sections 1-3 in Brown, LeMay, Bursten, & Murphy. 1. What product(s) might be expected to form when

More information

PREPARATION FOR CHEMISTRY LAB: PRECIPITATION

PREPARATION FOR CHEMISTRY LAB: PRECIPITATION 1 Name: Lab Instructor: PREPARATION FOR CHEMISTRY LAB: PRECIPITATION Solubility rules are given in your textbook. 1. Aqueous solutions of aluminum nitrate, barium acetate, and lithium sulfate are available.

More information

Chemical Reactions Chapter 8 Assignment & Problem Set

Chemical Reactions Chapter 8 Assignment & Problem Set Chemical Reactions Name Warm-Ups (Show your work for credit) Date 1. Date 2. Date 3. Date 4. Date 5. Date 6. Date 7. Date 8. Chemical Reactions 2 Study Guide: Things You Must Know Vocabulary (know the

More information

Types of Chemical Reactions and Electrolytes: A Demonstration

Types of Chemical Reactions and Electrolytes: A Demonstration Exercise 4 Page 1 Illinois Central College Chemistry 130 Laboratory Section Name Types of Chemical Reactions and Electrolytes: A Demonstration Objectives To study four classes of chemical reactions and

More information

Chapter 3 Stoichiometry: Ratios of Combination

Chapter 3 Stoichiometry: Ratios of Combination Chapter 3 Stoichiometry: Ratios of Combination 1 3.1 Molecular and Formula Masses 3.2 Percent Composition of Compounds 3.3 Chemical Equations 3.4 The Mole and Molar Mass 3.5 Combustion Analysis 3.6 Calculations

More information

Experiment 8 - Double Displacement Reactions

Experiment 8 - Double Displacement Reactions Experiment 8 - Double Displacement Reactions A double displacement reaction involves two ionic compounds that are dissolved in water. In a double displacement reaction, it appears as though the ions are

More information

LAW OF CONSERVATION OF MASS

LAW OF CONSERVATION OF MASS 295 LAW OF CONSERVATION OF MASS OBJECTIVES FOR THE EXPERIMENT The student will be able to do the following: 1. Write or identify a description of the Law of Conservation of Mass. 2. Given formulas for

More information

Solution Stoichiometry Quantitative Preparation of Aqueous Solutions

Solution Stoichiometry Quantitative Preparation of Aqueous Solutions Solution Stoichiometry Quantitative Preparation of Aqueous Solutions Introduction Page 1 of 11 In this week s lab, you and your lab partner will apply your prelab calculations to the preparation of aqueous

More information

Ideal Stoichiometric Calculations

Ideal Stoichiometric Calculations Section Main Ideas Balanced equations give amounts of reactants and products under ideal conditions Mole-to-gram calculations require two conversion factors Gram-to-mole conversions require the molar mass

More information

Stoichiometry: Calculations with Chemical Formulas and Equations. In this chapter. The Mole. Sponsored by Lavoisier & Avogadro.

Stoichiometry: Calculations with Chemical Formulas and Equations. In this chapter. The Mole. Sponsored by Lavoisier & Avogadro. Stoichiometry: Calculations with Chemical Formulas and Equations Sponsored by Lavoisier & Avogadro Chapter 3 In this chapter The mole concept. Relationships between chemical formulas, atomic masses and

More information

Stoichiometry: Calculations with Chemical Formulas and Equations. In this chapter

Stoichiometry: Calculations with Chemical Formulas and Equations. In this chapter Stoichiometry: Calculations with Chemical Formulas and Equations Sponsored by Lavoisier & Avogadro Chapter 3 In this chapter The mole concept. Relationships between chemical formulas, atomic masses and

More information

Solubility Product Constant, K sp

Solubility Product Constant, K sp Exercise 5 Page 1 Illinois Central College CHEMISTRY 132 Laboratory Section: Name: Solubility Product Constant, K sp Equipment 2-2500 ml burette 2-250 ml beakers 0300 M NaC 2 0200 M AgNO 3 ferric alum

More information

What is the Percent Copper in a Compound?

What is the Percent Copper in a Compound? Lab 9 Name What is the Percent Copper in a Compound? Pre-Lab Assignment Complete this pre-lab on this sheet. This written pre-lab is worth 15% (3 points) of your lab report grade and must be initialed

More information

Experiment 9 - Double Displacement Reactions

Experiment 9 - Double Displacement Reactions Experiment 9 - Double Displacement Reactions A double displacement reaction involves two ionic compounds that are dissolved in water. In a double displacement reaction, it appears as though the ions are

More information

Chapter 4: Solution Stoichiometry Cont. Aqueous Solutions

Chapter 4: Solution Stoichiometry Cont. Aqueous Solutions Chapter 4: Solution Stoichiometry Cont. 1 Aqueous Solutions Molarity (dilution calculations, solution stoichiometry); Solubility and Solubility Rules Molecular, Ionic and Net Ionic Equations Precipitation

More information

CSUS Department of Chemistry Experiment 4 Chem.1A

CSUS Department of Chemistry Experiment 4 Chem.1A Name: Section: Experiment 4: Synthesis of Alum Pre-laboratory Assignment (Read through the experiment before starting!) 1. a) What are the strong acid and strong base used in this synthesis? b) What should

More information

EXPERIMENT 15: AQUEOUS SOLUBILITIES OF IONIC COMPOUNDS

EXPERIMENT 15: AQUEOUS SOLUBILITIES OF IONIC COMPOUNDS PURPOSE EXPERIMENT 15: AQUEOUS SOLUBILITIES OF IONIC COMPOUNDS To determine which cation-anion combinations form water-soluble or water-insoluble salts. To formulate general solubility rules from the results

More information

Chapter 6. Chemical Calculations: Formula Masses, Moles, and Chemical Equations

Chapter 6. Chemical Calculations: Formula Masses, Moles, and Chemical Equations Chapter 6 Chemical Calculations: Formula Masses, Moles, and Chemical Equations Chapter 6 Chapter Outline 6.1 Formula masses 6.2 The mole: A counting unit for chemists 6.3 The mass of a mole 6.4 Chemical

More information

Stoichiometry Notes. Review of Moles. Determine the molar mass of Ca 3 (PO 4 ) 2. How many moles of H 2 O are in 9.87 grams of H 2 O?

Stoichiometry Notes. Review of Moles. Determine the molar mass of Ca 3 (PO 4 ) 2. How many moles of H 2 O are in 9.87 grams of H 2 O? Stoichiometry Notes Review of Moles Determine the molar mass of Ca 3 (PO 4 ) 2 How many moles of H 2 O are in 9.87 grams of H 2 O? How many molecules are in 87.9 grams of nitrogen dioxide? How many oxygen

More information

Periodic Trends and the Properties of Elements The Alkaline Earth Metals

Periodic Trends and the Properties of Elements The Alkaline Earth Metals Periodic Trends and the Properties of Elements The Alkaline Earth Metals Introduction: The periodic table is the most recognized symbol of chemistry across the world. It is a valuable tool that allows

More information

Chemical Reactions. Chemical equation

Chemical Reactions. Chemical equation Handout Kimia Dasar I 2013/2014 Chemical Reactions Chemical equation All chemical reactions take place according to a set of general principles that relate the amounts of materials consumed in a reaction

More information

EXPERIMENT 7 Reaction Stoichiometry and Percent Yield

EXPERIMENT 7 Reaction Stoichiometry and Percent Yield EXPERIMENT 7 Reaction Stoichiometry and Percent Yield INTRODUCTION Stoichiometry calculations are about calculating the amounts of substances that react and form in a chemical reaction. The word stoichiometry

More information

Using Solubility Rules to Predict Precipitate Formation

Using Solubility Rules to Predict Precipitate Formation iodide, I all others soluble 1.15 solubility a measure of the extent to which a solute dissolves in a solvent at a given temperature and pressure Using Solubility Rules to Predict Precipitate Formation

More information

Austin Peay State University Department of Chemistry CHEM 1111. Copper Cycle

Austin Peay State University Department of Chemistry CHEM 1111. Copper Cycle Cautions Nitric acid and sulfuric acid are toxic and oxidizers and may burn your skin. Nitrogen dioxide gas produced is hazardous if inhaled. Sodium hydroxide is toxic and corrosive and will cause burns

More information

Lab Handout. Introduction

Lab Handout. Introduction Lab Handout Lab 4. Conservation of Mass How Does the Total Mass of the Substances Formed as a Result of a Chemical Change Compare With the Total Mass of the Original Substances? Introduction Matter is

More information

Chemical Equations and Calculations

Chemical Equations and Calculations Chemical Equations and Calculations A chemical equation is a shorthand way of indicating what is going on in a chemical reaction. We could do it the long way Two molecules of Hydrogen gas react with one

More information

Foiled Again Single Replacement Reactions

Foiled Again Single Replacement Reactions Foiled Again Single Replacement Reactions SCIENTIFIC Introduction Watch aluminum foil disappear as it is added to a green-blue solution of copper(ii) chloride. Observe color changes, production of a gas,

More information

Laboratory 12: Properties of Solutions

Laboratory 12: Properties of Solutions Introduction Solutions are an important class of materials we each encounter daily. This experiment will probe the physical properties of solutions. Discussion A complete discussion of solutions can be

More information

Solubility Equilibria

Solubility Equilibria Every electrolyte (in aqueous solution), consists partly of active (in electrical and chemical relation), and partly of inactive molecules... Svante Arrhenius Solubility Equilibria Pure water is actually

More information

Sample Problem: Find the percentage composition of MgCO 3.

Sample Problem: Find the percentage composition of MgCO 3. Chemistry H: Form TR4.5A TEST 4 REVIEW Name Date Period Test Review # 4 Formula Mass. The masses of ionic and covalent compounds are found the same way from the formula. The atomic masses of the elements

More information

What is the Compound in Mr. Coffee Cleaner? 1

What is the Compound in Mr. Coffee Cleaner? 1 What is the Compound in Mr. Coffee Cleaner? 1 A. Introduction HOW MR. COFFEE CLEANER WORKS Mr. Coffee sells a cleaner that is supposed to clean the scale that forms in coffee pots and tea kettles when

More information

RELATING MOLES TO COEFFICIENTS OF A CHEMICAL EQUATION

RELATING MOLES TO COEFFICIENTS OF A CHEMICAL EQUATION RELATING MOLES TO COEFFICIENTS OF A CHEMICAL EQUATION Pre-Lab Discussion The mole is defined as Avogadro s number (6.02 X 10 23 ) of particles. These particles may be atoms, molecules, formula units, ions,

More information

Chapter 6, Lesson 3: Forming a Precipitate

Chapter 6, Lesson 3: Forming a Precipitate Chapter 6, Lesson 3: Forming a Precipitate Key Concepts The ions or molecules in two solutions can react to form a solid. A solid formed from two solutions is called a precipitate. Summary Students will

More information

Double Replacement Reactions and Solubility

Double Replacement Reactions and Solubility Page / - Net Ionic Equations Introduction Precipitation reactions, a type of double replacement reaction, are widely used to prepare new compounds and analyze their purity. Precipitation reactions occur

More information

Year 10 Chemistry Exam June 2012

Year 10 Chemistry Exam June 2012 Year 10 Chemistry Exam June 2012 Answer the multiple choice questions on the multiple choice sheet provided 1. The table below shows details of several particles. Atomic number Mass number Number of Number

More information

Exam 2, Ch 4-6 October 16, Points

Exam 2, Ch 4-6 October 16, Points Chem 120 Name Exam 2, Ch 4-6 October 16, 2008 100 Points Please follow the instructions for each section of the exam. Show your work on all mathematical problems. Provide answers with the correct units

More information

Solubility Rules and Net Ionic Equations

Solubility Rules and Net Ionic Equations Solubility Rules and Net Ionic Equations Why? Solubility of a salt depends upon the type of ions in the salt. Some salts are soluble in water and others are not. When two soluble salts are mixed together

More information

Set 4 Acid- Bases & Salts Perfect Score F4 2010

Set 4 Acid- Bases & Salts Perfect Score F4 2010 ACID AND BASES 1. An acid is a chemical compound that produce hydrogen ion, H + or hydroxonium, H 3 O + when dissolves in water. HCl + H 2 O H 3 O + + Cl - H 2 O HCl H + + Cl - 2. An acid shows its acidic

More information

STOICHIOMETRY II UNIT

STOICHIOMETRY II UNIT STOICHIOMETRY II UNIT Assignment #1 (Conversions with compounds) 1. Convert 1.806 x 10 23 molecules of Cl2 to moles. 2. Convert 1000 molecules of P4O10 to moles. 3. Convert 360 grams of NH3 (ammonia gas)

More information

Stoichiometry Limiting Reagent Laboratory. Chemistry 118 Laboratory University of Massachusetts, Boston

Stoichiometry Limiting Reagent Laboratory. Chemistry 118 Laboratory University of Massachusetts, Boston Chemistry 118 Laboratory University of Massachusetts, Boston STOICHIOMETRY - LIMITING REAGENT -----------------------------------------------------------------------------------------------------------------------------

More information

B. chemical equation - set of symbols and numbers which represent a chemical change. Reactants Products

B. chemical equation - set of symbols and numbers which represent a chemical change. Reactants Products 1 I. Introduction A. chemical reaction any chemical change B. chemical equation set of symbols and numbers which represent a chemical change 1. reactants what you begin with 2. products what you end up

More information

Redox Chemistry EQUIPMENT

Redox Chemistry EQUIPMENT Redox Chemistry In the first week of this experiment you will synthesize a sample of the compound copper(ii) glycinate monohydrate, which you will analyze the next week. You will also use standard reduction

More information

Section B: Some Essential Background Chemistry

Section B: Some Essential Background Chemistry Section B: Some Essential Background Chemistry Soluble and insoluble salts The importance of knowing whether a salt is soluble or insoluble in water You will remember that acids react with carbonates to

More information

ALE 17. Equilibria of Slightly Soluble Compounds. How is the solubility of a salt related to its solubility product constant?

ALE 17. Equilibria of Slightly Soluble Compounds. How is the solubility of a salt related to its solubility product constant? Name Chem 163 Section: Team Number: ALE 17. Equilibria of Slightly Soluble Compounds (Reference: 19.3 Silberberg 5 th edition) How is the solubility of a salt related to its solubility product constant?

More information

Chemical Reactions: An Introduction

Chemical Reactions: An Introduction Chapter 4 Chemical Reactions: An Introduction Concept Check 4.1 LiI(s) and CH 3 OH(l) are each introduced into a separate beaker containing water. Using the drawings shown here, label each beaker with

More information

Subscripts and Coefficients Give Different Information

Subscripts and Coefficients Give Different Information Chapter 3: Stoichiometry Goal is to understand and become proficient at working with: 1. Chemical equations (Balancing REVIEW) 2. Some simple patterns of reactivity 3. Formula weights (REVIEW) 4. Avogadro's

More information

Outline. 6.1 Chemical Equations. 6.2 Balancing Chemical Equations

Outline. 6.1 Chemical Equations. 6.2 Balancing Chemical Equations Outline 6.1 Chemical Equations 6.2 Balancing Chemical Equations 6.3 Avogadro s Number and the Mole 6.4 Gram Mole Conversions 6.5 Mole Relationships and Chemical Equations 6.6 Mass Relationships and Chemical

More information

CHM152LL Solution Chemistry Worksheet

CHM152LL Solution Chemistry Worksheet Name: Section: CHM152LL Solution Chemistry Worksheet Many chemical reactions occur in solution. Solids are often dissolved in a solvent and mixed to produce a chemical reaction that would not occur if

More information

Chapter 4 Notes - Types of Chemical Reactions and Solution Chemistry

Chapter 4 Notes - Types of Chemical Reactions and Solution Chemistry AP Chemistry A. Allan Chapter 4 Notes - Types of Chemical Reactions and Solution Chemistry 4.1 Water, the Common Solvent A. Structure of water 1. Oxygen's electronegativity is high (3.5) and hydrogen's

More information

CHEMICAL EQUATIONS AND REACTION TYPES

CHEMICAL EQUATIONS AND REACTION TYPES CHEMICAL EQUATIONS AND REACTION TYPES The purpose of this laboratory exercise is to develop skills in writing and balancing chemical equations. The relevance of this exercise is illustrated by a series

More information

CHM 130LL: Double Replacement Reactions

CHM 130LL: Double Replacement Reactions CHM 130LL: Double Replacement Reactions One of the main purposes of chemistry is to transform one set of chemicals (the reactants) into another set of chemicals (the products) via a chemical reaction:

More information

Chemical calculations

Chemical calculations Chemical calculations Stoichiometry refers to the quantities of material which react according to a balanced chemical equation. Compounds are formed when atoms combine in fixed proportions. E.g. 2Mg +

More information

Week 3 July 22, 2016 Worksheet. Review III. 1 mol = a) 10.0 g Na b) 10.0 g Fe c) 10.0 g Ag d) 10.0 g Cu e) 10.0 g Ba

Week 3 July 22, 2016 Worksheet. Review III. 1 mol = a) 10.0 g Na b) 10.0 g Fe c) 10.0 g Ag d) 10.0 g Cu e) 10.0 g Ba Review III = 6.022 10 23 1. Which sample contains the greatest number of atoms? a) 10.0 g Na b) 10.0 g Fe c) 10.0 g Ag d) 10.0 g Cu e) 10.0 g Ba 10.0 g Na 10.0 g Fe Na 22.99 g Na 6.022 1023 atoms = 2.62

More information

The Mole Concept. The Mole. Masses of molecules

The Mole Concept. The Mole. Masses of molecules The Mole Concept Ron Robertson r2 c:\files\courses\1110-20\2010 final slides for web\mole concept.docx The Mole The mole is a unit of measurement equal to 6.022 x 10 23 things (to 4 sf) just like there

More information

CHEMICAL EQUATIONS and REACTION TYPES

CHEMICAL EQUATIONS and REACTION TYPES 31 CHEMICAL EQUATIONS and REACTION TYPES The purpose of this laboratory exercise is to develop skills in writing and balancing chemical equations. The relevance of this exercise is illustrated by a series

More information

Honors Chemistry: Unit 6 Test Stoichiometry PRACTICE TEST ANSWER KEY Page 1. A chemical equation. (C-4.4)

Honors Chemistry: Unit 6 Test Stoichiometry PRACTICE TEST ANSWER KEY Page 1. A chemical equation. (C-4.4) Honors Chemistry: Unit 6 Test Stoichiometry PRACTICE TEST ANSWER KEY Page 1 1. 2. 3. 4. 5. 6. Question What is a symbolic representation of a chemical reaction? What 3 things (values) is a mole of a chemical

More information

Observing, Writing, and Predicting Chemical Reactions Name:

Observing, Writing, and Predicting Chemical Reactions Name: Chem 110 Lab Clark College Observing, Writing, and Predicting Chemical Reactions Name: Partner s Name: Introduction As someone taking a chemistry class, you will need to understand chemical formulas, chemical

More information

Tutorial 4 SOLUTION STOICHIOMETRY. Solution stoichiometry calculations involve chemical reactions taking place in solution.

Tutorial 4 SOLUTION STOICHIOMETRY. Solution stoichiometry calculations involve chemical reactions taking place in solution. T-27 Tutorial 4 SOLUTION STOICHIOMETRY Solution stoichiometry calculations involve chemical reactions taking place in solution. Of the various methods of expressing solution concentration the most convenient

More information

experiment5 Understanding and applying the concept of limiting reagents. Learning how to perform a vacuum filtration.

experiment5 Understanding and applying the concept of limiting reagents. Learning how to perform a vacuum filtration. 81 experiment5 LECTURE AND LAB SKILLS EMPHASIZED Synthesizing an organic substance. Understanding and applying the concept of limiting reagents. Determining percent yield. Learning how to perform a vacuum

More information

ANALYSIS OF PHOSPHORUS IN PLANT FOOD

ANALYSIS OF PHOSPHORUS IN PLANT FOOD Experiment 10 ANALYSIS OF PHOSPHORUS IN PLANT FOOD Adapted by Ross S. Nord, Eastern Michigan University, from Analysis of Phosphorous in Fertilizer found at http://chem.lapeer.org/chem2docs/phosphateanal.html

More information

Observing, Writing, and Predicting Chemical Reactions Name:

Observing, Writing, and Predicting Chemical Reactions Name: Chem 110 Lab Clark College Observing, Writing, and Predicting Chemical Reactions Name: Partner s Name: Introduction As someone taking a chemistry class, you will need to understand chemical formulas, chemical

More information

IB Chemistry 1 Mole. One atom of C-12 has a mass of 12 amu. One mole of C-12 has a mass of 12 g. Grams we can use more easily.

IB Chemistry 1 Mole. One atom of C-12 has a mass of 12 amu. One mole of C-12 has a mass of 12 g. Grams we can use more easily. The Mole Atomic mass units and atoms are not convenient units to work with. The concept of the mole was invented. This was the number of atoms of carbon-12 that were needed to make 12 g of carbon. 1 mole

More information

Chemistry 1215 Experiment #10 The Reaction of Zinc and Iodine: The Combination of Two Elements

Chemistry 1215 Experiment #10 The Reaction of Zinc and Iodine: The Combination of Two Elements Chemistry 1215 Experiment #10 The Reaction of Zinc and Iodine: The Combination of Two Elements Objective The objective of this experiment is to perform a combination reaction by reacting elemental zinc

More information

Chapter 3. Stoichiometry: Ratios of Combination. Insert picture from First page of chapter. Copyright McGraw-Hill 2009 1

Chapter 3. Stoichiometry: Ratios of Combination. Insert picture from First page of chapter. Copyright McGraw-Hill 2009 1 Chapter 3 Insert picture from First page of chapter Stoichiometry: Ratios of Combination Copyright McGraw-Hill 2009 1 3.1 Molecular and Formula Masses Molecular mass - (molecular weight) The mass in amu

More information

Ionic Reactions in Aqueous Solutions Prelab. 4. Identify the cation and anion, with charges, in each compound in question 3.

Ionic Reactions in Aqueous Solutions Prelab. 4. Identify the cation and anion, with charges, in each compound in question 3. Ionic Reactions in Aqueous Solutions Prelab Name Total /10 SHOW ALL WORK NO WORK = NO CREDIT 1. What is the purpose of this experiment? 2. Give the definition of a precipitation reaction. 3. Using the

More information

Concept Check: Chemical Equations and Calculations. Dalton? Aluminum nitrate dinitrogen octafluoride Co 2. ) 3 Li 2 (CO 3

Concept Check: Chemical Equations and Calculations. Dalton? Aluminum nitrate dinitrogen octafluoride Co 2. ) 3 Li 2 (CO 3 Concept Check: A scientific is a concise statement or equation that summarizes the results of a series of experiments. a. Theory b. Law c. Trend d. Hypothesis e. Experiment Which of the following has the

More information

QUALITATIVE ANALYSIS

QUALITATIVE ANALYSIS QUALITATIVE ANALYSIS Objectives: 1. To perform spot test precipitation reactions. 2. To write and balance precipitation reaction equations. 3. To learn how to balance equations. 4. To learn the solubility

More information

Chemical Names and Formulas

Chemical Names and Formulas Chemical Names and Formulas Goals Write chemical names and formulas of common chemical compounds. Describe the colors and textures of common ionic compounds. Synthesize chemical compounds and write their

More information

Chemical Equations. Before You Read. How are chemical changes and chemical reactions linked? How is a chemical reaction represented?

Chemical Equations. Before You Read. How are chemical changes and chemical reactions linked? How is a chemical reaction represented? Chemical Equations Textbook pages 202 215 Section 4.3 Summary Before You Read What do you already know about chemical s? Write your ideas in the lines below. Create a Table Create a table that outlines

More information

THE MOLE (a counting unit).again!

THE MOLE (a counting unit).again! THE MOLE (a counting unit).again! A mole represents a set or group, much in the same way that a dozen represents a set of twelve. 1 dozen eggs = 12 eggs; 1 mol eggs = 6.022 10 23 eggs 1 dozen carbon atoms

More information

COPYRIGHT FOUNTAINHEAD PRESS

COPYRIGHT FOUNTAINHEAD PRESS Law of Multiple Proportions Objectives: Materials: To determine the chloride content of two different compounds by volumetric analysis; to use the data collected to demonstrate the Law of Multiple Proportions.

More information

CHEM 151 CHEMICAL REACTIONS OF COPPER Fall 2008

CHEM 151 CHEMICAL REACTIONS OF COPPER Fall 2008 CHEM 151 CHEMICAL REACTIONS OF COPPER Fall 2008 Fill-in!!! Pre-lab attached (p 9) Lecture Instructor Stamp Here Name Partner Date Before you begin, read the following section in your Laboratory Handbook:

More information

2. In a double displacement reaction, 3. In the chemical equation, H 2 O 2 H 2 + O 2, the H 2 O 2 is a

2. In a double displacement reaction, 3. In the chemical equation, H 2 O 2 H 2 + O 2, the H 2 O 2 is a What are the missing coefficients for the skeleton equation below? Al 2 (SO 4 ) 3 + KOH Al(OH) 3 + K 2 SO 4 2. In a double displacement reaction, A. 1,6,2,3 B. 2,12,4,6 C. 1,3,2,3 D. 4,6,2,3 E. 2,3,1,1

More information

Phosphorous(phosphate) determination in Plant Food *

Phosphorous(phosphate) determination in Plant Food * Phosphorous(phosphate) determination in Plant Food * This experiment uses a technique known as gravimetric analysis to determine how much phosphorous (as a weight % P 2 O 5 ) there is in samples of plant

More information

SCH3UI-02 Final Examination Review (Fall 2014)

SCH3UI-02 Final Examination Review (Fall 2014) SCH3UI-02 Final Examination Review (Fall 2014) 1. Chlorine has an atomic number of 17. Create a Bohr Rutherford diagram of a Cl-35 atom. To achieve a stable arrangement, is this atom most likely to gain

More information

Swap the cations of the reactants to form the products, which are two new ionic compounds: The products will be sodium nitrate and silver carbonate.

Swap the cations of the reactants to form the products, which are two new ionic compounds: The products will be sodium nitrate and silver carbonate. Predicting Products of Precipitation Reactions: Solubility Rules (Small-scale experiment adapted from Waterman's Chemistry lab manual, #23) Goals Observe and record precipitation reactions. Derive general

More information

Chapter 3 Chemical Reactions and Reaction Stoichiometry. 許富銀 ( Hsu Fu-Yin)

Chapter 3 Chemical Reactions and Reaction Stoichiometry. 許富銀 ( Hsu Fu-Yin) Chapter 3 Chemical Reactions and Reaction Stoichiometry 許富銀 ( Hsu Fu-Yin) 1 Stoichiometry The study of the numerical relationship between chemical quantities in a chemical reaction is called stoichiometry.

More information

"Believe in yourself. You must do that which you think you cannot." --Eleanor Roosevelt--

Believe in yourself. You must do that which you think you cannot. --Eleanor Roosevelt-- CHEMISTRY 101 Hour Exam II October 28, 2014 Adams/Esbenshade Name Signature Section "Believe in yourself. You must do that which you think you cannot." --Eleanor Roosevelt-- This exam contains 17 questions

More information

Calculations and Chemical Equations. Example: Hydrogen atomic weight = 1.008 amu Carbon atomic weight = 12.001 amu

Calculations and Chemical Equations. Example: Hydrogen atomic weight = 1.008 amu Carbon atomic weight = 12.001 amu Calculations and Chemical Equations Atomic mass: Mass of an atom of an element, expressed in atomic mass units Atomic mass unit (amu): 1.661 x 10-24 g Atomic weight: Average mass of all isotopes of a given

More information

1. Chemical reaction = process by which one or more substances are changed into one or more different substances (atoms are rearranged)

1. Chemical reaction = process by which one or more substances are changed into one or more different substances (atoms are rearranged) 1. Chemical reaction = process by which one or more substances are changed into one or more different substances (atoms are rearranged) a) reactants = original substances(written to the left of the arrow

More information