DETERMINING THE ENTHALPY OF FORMATION OF CaCO 3
|
|
- Barbara Hudson
- 7 years ago
- Views:
Transcription
1 DETERMINING THE ENTHALPY OF FORMATION OF CaCO 3 Standard Enthalpy Change Standard Enthalpy Change for a reaction, symbolized as H 0 298, is defined as The enthalpy change when the molar quantities of reactants shown in a balanced chemical equation completely react to from products under standard conditions. Standard conditions are as follows: - a pressure of 1 atmosphere - a temperature of 298 K - if solution is used, 1M is specified. - Elements or compounds in their normal stable state Example H 2(g) + 1/2 O 2(g) H 2 O (l) H 0 = kj mol -1 When one mole of hydrogen and half mole of oxygen react to form one mole water, kj of heat are evolved under standard conditions. This is an exothermic reaction. All the substance involved must be in their normal physical states under standard conditions. The enthalpy of all elements in their most stable form and standard state is conventionally taken as zero. For example, H [O 2(g) ] = 0 H 0 298[Na (s) ]=0 Therefore, the standard enthalpy of formation of a compound represents the enthalpy content of the compound. Hess s Law The law of conservation of energy states that energy can be neither be created or destroyed, though one form of energy can be converted to another form. This law therefore implies that the total energy content ( in the system ) is constant. Based on it, Hess s law arises. Hess s Law: The standard enthalpy change of reaction depends only on the difference between the standard enthalpy of the reactants and the standard enthalpy of the products, and not no the route by which the reaction occurs. In other words, for processes involving several stages, the enthalpy change for the reaction is equal to the algebraic sum of the enthalpy change for each intermediate stage. Page 1
2 The enthalpy change for the oxidation of carbon (graphite) to carbon dioxide is the same whether it is carried out Route A ( 1 stage ) or Route B ( 2 stages) Route A: C (s) + O 2(g) CO 2(g) H a = kj mol -1 Route B: C (s) + 1/2 O 2(g) CO (g) H b1 = kj mol -1 CO (g) + 1/2 O 2(g) CO 2(g) H b2 = kj mol -1 H b1 + H b2 = (-110.5) + (-283.0) = kj mol -1 The Use of Hess s Law in determining Enthalpy Changes Some reactions proceed very slowly or involve formation of side products. Hess s Law can be used to determine the enthalpy changes of such reactions which cannot be determined directly by calorimetry experiments. Page 2
3 The molar enthalpy of formation, H f, is defined as the enthalpy change when 1 mole of a compound is formed directly from its elements. Although some compounds (e.g., MgO) can be formed by direct synthesis from the elements, many cannot. Calcium carbonate is one of them. Below is the chemical equation representing the formation of 1 mole of CaCO 3 :- Ca (s) + C (s) + 1½ O 2 (g) CaCO 3 (s) The enthalpy change for this reaction can be found indirectly from reactions which can actually be carried out in the lab and then applying Hess s Law. Both calcium metal and calcium carbonate react with dilute hydrochloric acid to form a solution of calcium chloride. In addition, calcium metal forms H 2 gas and calcium carbonate forms CO 2 and H 2 O. The enthalpy changes for these two reactions can be measured relatively easily in the lab. For the calculation of H f for CaCO 3, two more pieces of data are needed, i.e., the enthalpies of formation of water and carbon dioxide. Page 3
4 Page 4
5 METHOD 1) H 1 for Ca + HCl Weigh out accurately about 1g of calcium metal into a weighing bottle and record the mass. Weigh a polystyrene calorimeter cup and record the mass. Use a measuring cylinder to add 100cm 3 of 1M HCl. Reweigh the cup with the acid and record the mass. Place the polystyrene cup inside a beaker for support, as shown in the diagram opposite. Place the thermometer in the acid and start the stop-clock. Record the temperature every minute for 3 minutes. On the 4 th minute, quickly add all the calcium metal and stir to mix thoroughly, keeping the lid on top of the cup. Record the temperature every minute from the 5 th minute for a further 10 minutes. Stir the solution before each reading. Empty and rinse the cup and thermometer and dry them with paper towel. 2) H 2 for CaCO 3 + HCl Weigh out accurately between 2 and 3g of calcium carbonate powder into a clean weighing bottle and record the mass. Using the same polystyrene cup as before, add a fresh lot of 100cm 3 of 1M HCl using the measuring cylinder, weigh again and record the mass. Repeat the steps in experiment 1, recording the temperature every minute and adding the solid on the 4 th minute. Empty and rinse the cup and thermometer and place them on the wet tray. Clear away all the apparatus and leave your bench clean and tidy. Page 5
6 EXPERIMENT 1 EXPERIMENT 2 Mass of calcium metal Mass of calcium carbonate Mass of empty cup Mass of cup plus acid Mass of empty cup Mass of cup plus acid Mass of acid 1 (M 1 ) Mass of acid 2 (M 2 ) TIME (minutes) TEMPERATURE ( O C) EXPERIMENT 1 EXPERIMENT 2 4 ADD THE SOLID FINDING THE TEMPERATURE CHANGES Plot two separate graphs of temperature against time, one for each experiment. Extrapolate the points find out the instantaneous temperature change at the 4 th minute in each reaction. Call these t 1 and t 2. Page 6
7 CALCULATING THE ENERGY CHANGES Take the Specific Heat Capacity (c) for the solutions to be 4.18 J.g -1. O C -1 Take the mass of the solutions to be the mass of acid used in each experiment Ignore the sign of the temperature change (rise or drop) just use the numerical value 1) For Ca metal Heat change = mass of solution 1 c t 1 =. J = kj Moles of Ca = mass of Ca Atomic Wt. (At.Wt. for Ca = 40.1) = Energy per mole = Heat change number of moles =. kj.mol -1 Now decide whether the reaction was exothermic (temperature rise) or endothermic (temperature drop). Use the correct sign convention to write your value for the enthalpy change for this reaction below:- H 1 =.. kj.mol -1 2) For CaCO 3 Heat change = mass of solution 2 c t 2 =. J = kj Moles of CaCO 3 = mass of CaCO 3 Molar Mass (Molar Mass = 100.1) = Energy per mole = Heat change number of moles =. kj.mol -1 Now decide whether the reaction was exothermic or endothermic. Use the correct sign convention to write your value for the enthalpy change for this reaction below:- H 2 =.. kj.mol -1 3) Use Hess Law and your values for H 1 and H 2 and the enthalpies of formation for water and carbon dioxide to calculate the enthalpy of formation for CaCO 3. H 2 (g) + ½O 2 (g) H 2 O (l) H f = kj.mol -1 (call this H 3 ) C (s) + O 2 (g) CO 2 (g) H f = kj.mol -1 (call this H 4 ) Page 7
Transfer of heat energy often occurs during chemical reactions. A reaction
Chemistry 111 Lab: Thermochemistry Page I-3 THERMOCHEMISTRY Heats of Reaction The Enthalpy of Formation of Magnesium Oxide Transfer of heat energy often occurs during chemical reactions. A reaction may
More informationThermochemistry: Calorimetry and Hess s Law
Thermochemistry: Calorimetry and Hess s Law Some chemical reactions are endothermic and proceed with absorption of heat while others are exothermic and proceed with an evolution of heat. The magnitude
More informationBomb Calorimetry. Example 4. Energy and Enthalpy
Bomb Calorimetry constant volume often used for combustion reactions heat released by reaction is absorbed by calorimeter contents need heat capacity of calorimeter q cal = q rxn = q bomb + q water Example
More informationthermometer as simple as a styrofoam cup and a thermometer. In a calorimeter the reactants are placed into the
Thermochemistry Readin assinment: Chan, Chemistry 10 th edition, pp. 249-258. Goals We will become familiar with the principles of calorimetry in order to determine the heats of reaction for endothermic
More informationThermochemistry I: Endothermic & Exothermic Reactions
THERMOCHEMISTRY I 77 Thermochemistry I: Endothermic & Exothermic Reactions OBJECTIVES: Learn elementary concepts of calorimetry and thermochemistry Practice techniques of careful temperature, mass, and
More informationThe Empirical Formula of a Compound
The Empirical Formula of a Compound Lab #5 Introduction A look at the mass relationships in chemistry reveals little order or sense. The ratio of the masses of the elements in a compound, while constant,
More informationEXPERIMENT 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 informationApparatus error for each piece of equipment = 100 x margin of error quantity measured
1) Error Analysis Apparatus Errors (uncertainty) Every time you make a measurement with a piece of apparatus, there is a small margin of error (i.e. uncertainty) in that measurement due to the apparatus
More informationSUGGESTION ANSWER SCHEME CHAPTER 8: THERMOCHEMISTRY. 1 (a) Use the data in the table below to answer the following questions:
SUGGESTION ANSWER SCHEME CHAPTER 8: THERMOCHEMISTRY ANSWER SCHEME UPS 2004/2005 SK027 1 (a) Use the data in the table below to answer the following questions: Enthalpy change ΔH (kj/mol) Atomization energy
More informationThe energy level diagram for this reaction is shown below.
Q. Methanol can be made when methane reacts with oxygen. (a) The energy level diagram for this reaction is shown below. (i) What is the energy change represented by A? () (ii) Use the energy level diagram
More informationThermochemical equations allow stoichiometric calculations.
CHEM 1105 THERMOCHEMISTRY 1. Change in Enthalpy ( H) Heat is evolved or absorbed in all chemical reactions. Exothermic reaction: heat evolved - heat flows from reaction mixture to surroundings; products
More informationExperiment 6 Coffee-cup Calorimetry
6-1 Experiment 6 Coffee-cup Calorimetry Introduction: Chemical reactions involve the release or consumption of energy, usually in the form of heat. Heat is measured in the energy units, Joules (J), defined
More informationHEAT OF FORMATION OF AMMONIUM NITRATE
303 HEAT OF FORMATION OF AMMONIUM NITRATE OBJECTIVES FOR THE EXPERIMENT The student will be able to do the following: 1. Calculate the change in enthalpy (heat of reaction) using the Law of Hess. 2. Find
More informationUnit 6 The Mole Concept
Chemistry Form 3 Page 62 Ms. R. Buttigieg Unit 6 The Mole Concept See Chemistry for You Chapter 28 pg. 352-363 See GCSE Chemistry Chapter 5 pg. 70-79 6.1 Relative atomic mass. The relative atomic mass
More informationChemical Reactions Practice Test
Chemical Reactions Practice Test Chapter 2 Name Date Hour _ Multiple Choice Identify the choice that best completes the statement or answers the question. 1. The only sure evidence for a chemical reaction
More informationChemical Calculations: Formula Masses, Moles, and Chemical Equations
Chemical Calculations: Formula Masses, Moles, and Chemical Equations Atomic Mass & Formula Mass Recall from Chapter Three that the average mass of an atom of a given element can be found on the periodic
More informationPractical 1: Measure the molar volume of a gas
Practical Student sheet Practical : Wear eye protection. Ensure the delivery tube does not become blocked. Ethanoic acid will sting if it gets into cuts in the skin. Equipment boiling tube stand and clamp
More informationChemistry B11 Chapter 4 Chemical reactions
Chemistry B11 Chapter 4 Chemical reactions Chemical reactions are classified into five groups: A + B AB Synthesis reactions (Combination) H + O H O AB A + B Decomposition reactions (Analysis) NaCl Na +Cl
More informationPREPARATION FOR CHEMISTRY LAB: COMBUSTION
1 Name: Lab Instructor: PREPARATION FOR CHEMISTRY LAB: COMBUSTION 1. What is a hydrocarbon? 2. What products form in the complete combustion of a hydrocarbon? 3. Combustion is an exothermic reaction. What
More information1. Thermite reaction 2. Enthalpy of reaction, H 3. Heating/cooling curves and changes in state 4. More thermite thermodynamics
Chem 105 Fri 10-23-09 1. Thermite reaction 2. Enthalpy of reaction, H 3. Heating/cooling curves and changes in state 4. More thermite thermodynamics 10/23/2009 1 Please PICK UP your graded EXAM in front.
More informationChapter 3: Stoichiometry
Chapter 3: Stoichiometry Key Skills: Balance chemical equations Predict the products of simple combination, decomposition, and combustion reactions. Calculate formula weights Convert grams to moles and
More informationIB Chemistry. DP Chemistry Review
DP Chemistry Review Topic 1: Quantitative chemistry 1.1 The mole concept and Avogadro s constant Assessment statement Apply the mole concept to substances. Determine the number of particles and the amount
More informationUNIT 1 THERMOCHEMISTRY
UNIT 1 THERMOCHEMISTRY THERMOCHEMISTRY LEARNING OUTCOMES Students will be expected to: THERMOCHEMISTRY STSE analyse why scientific and technological activities take place in a variety individual and group
More informationIntroductory Chemistry, 3 rd Edition Nivaldo Tro. Roy Kennedy Massachusetts Bay Community College Wellesley Hills, Maqqwertd ygoijpk[l
Introductory Chemistry, 3 rd Edition Nivaldo Tro Quantities in Car an octane and oxygen molecules and carbon dioxide and water Chemical Reactions Roy Kennedy Massachusetts Bay Community College Wellesley
More information1. What is the molecular formula of a compound with the empirical formula PO and a gram-molecular mass of 284 grams?
Name: Tuesday, May 20, 2008 1. What is the molecular formula of a compound with the empirical formula PO and a gram-molecular mass of 284 grams? 2 5 1. P2O 5 3. P10O4 2. P5O 2 4. P4O10 2. Which substance
More informationExp 13 Volumetric Analysis: Acid-Base titration
Exp 13 Volumetric Analysis: Acid-Base titration Exp. 13 video (time: 47:17 minutes) Titration - is the measurement of the volume of a standard solution required to completely react with a measured volume
More informationThermodynamics. Thermodynamics 1
Thermodynamics 1 Thermodynamics Some Important Topics First Law of Thermodynamics Internal Energy U ( or E) Enthalpy H Second Law of Thermodynamics Entropy S Third law of Thermodynamics Absolute Entropy
More informationSummer Holidays Questions
Summer Holidays Questions Chapter 1 1) Barium hydroxide reacts with hydrochloric acid. The initial concentration of the 1 st solution its 0.1M and the volume is 100ml. The initial concentration of the
More informationChapter 3. Chemical Reactions and Reaction Stoichiometry. Lecture Presentation. James F. Kirby Quinnipiac University Hamden, CT
Lecture Presentation Chapter 3 Chemical Reactions and Reaction James F. Kirby Quinnipiac University Hamden, CT The study of the mass relationships in chemistry Based on the Law of Conservation of Mass
More informationDetermination of the enthalpy of combustion using a bomb calorimeter TEC
Determination of the enthalpy of TEC Related concepts First law of thermodynamics, Hess s law of constant heat summation, enthalpy of combustion, enthalpy of formation, heat capacity. Principle The bomb
More informationSUPPLEMENTARY TOPIC 3 ENERGY AND CHEMICAL REACTIONS
SUPPLEMENTARY TOPIC 3 ENERGY AND CHEMICAL REACTIONS Rearranging atoms. In a chemical reaction, bonds between atoms in one or more molecules (reactants) break and new bonds are formed with other atoms to
More informationEXPERIMENT 12: Empirical Formula of a Compound
EXPERIMENT 12: Empirical Formula of a Compound INTRODUCTION Chemical formulas indicate the composition of compounds. A formula that gives only the simplest ratio of the relative number of atoms in a compound
More informationHonors 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 informationIB 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 informationUnit 5 Practice Test. Name: Class: Date: Multiple Choice Identify the choice that best completes the statement or answers the question.
Name: Class: Date: Unit 5 Practice Test Multiple Choice Identify the choice that best completes the statement or answers the question. 1) The internal energy of a system is always increased by. A) adding
More informationMixtures and Pure Substances
Unit 2 Mixtures and Pure Substances Matter can be classified into two groups: mixtures and pure substances. Mixtures are the most common form of matter and consist of mixtures of pure substances. They
More informationChapter 8 - Chemical Equations and Reactions
Chapter 8 - Chemical Equations and Reactions 8-1 Describing Chemical Reactions I. Introduction A. Reactants 1. Original substances entering into a chemical rxn B. Products 1. The resulting substances from
More information7-5.5. Translate chemical symbols and the chemical formulas of common substances to show the component parts of the substances including:
7-5.5 Translate chemical symbols and the chemical formulas of common substances to show the component parts of the substances including: NaCl [salt], H 2 O [water], C 6 H 12 O 6 [simple sugar], O 2 [oxygen
More informationDetermination 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 informationChemical reactions allow living things to grow, develop, reproduce, and adapt.
Section 2: Chemical reactions allow living things to grow, develop, reproduce, and adapt. K What I Know W What I Want to Find Out L What I Learned Essential Questions What are the parts of a chemical reaction?
More informationExperiment 12- Classification of Matter Experiment
Experiment 12- Classification of Matter Experiment Matter can be classified into two groups: mixtures and pure substances. Mixtures are the most common form of matter and consist of mixtures of pure substances.
More informationHow To Calculate Mass In Chemical Reactions
We have used the mole concept to calculate mass relationships in chemical formulas Molar mass of ethanol (C 2 H 5 OH)? Molar mass = 2 x 12.011 + 6 x 1.008 + 1 x15.999 = 46.069 g/mol Mass percentage of
More informationEnergy and Chemical Reactions. Characterizing Energy:
Energy and Chemical Reactions Energy: Critical for virtually all aspects of chemistry Defined as: We focus on energy transfer. We observe energy changes in: Heat Transfer: How much energy can a material
More informationACID-BASE TITRATIONS: DETERMINATION OF CARBONATE BY TITRATION WITH HYDROCHLORIC ACID BACKGROUND
#3. Acid - Base Titrations 27 EXPERIMENT 3. ACID-BASE TITRATIONS: DETERMINATION OF CARBONATE BY TITRATION WITH HYDROCHLORIC ACID BACKGROUND Carbonate Equilibria In this experiment a solution of hydrochloric
More informationChemical Calculations: The Mole Concept and Chemical Formulas. AW Atomic weight (mass of the atom of an element) was determined by relative weights.
1 Introduction to Chemistry Atomic Weights (Definitions) Chemical Calculations: The Mole Concept and Chemical Formulas AW Atomic weight (mass of the atom of an element) was determined by relative weights.
More informationGeneral Chemistry I (FC, 09-10) Lab #3: The Empirical Formula of a Compound. Introduction
General Chemistry I (FC, 09-10) Introduction A look at the mass relationships in chemistry reveals little order or sense. The ratio of the masses of the elements in a compound, while constant, does not
More informationCHEMICAL REACTIONS OF COPPER AND PERCENT YIELD KEY
CHEMICAL REACTIONS OF COPPER AND PERCENT YIELD Objective To gain familiarity with basic laboratory procedures, some chemistry of a typical transition element, and the concept of percent yield. Apparatus
More informationStoichiometry Limiting Reagent Laboratory. Chemistry 118 Laboratory University of Massachusetts, Boston
Chemistry 118 Laboratory University of Massachusetts, Boston STOICHIOMETRY - LIMITING REAGENT --------------------------------------------------------------------------------------------------------------------------------------------
More informationAdiabatic Bomb Calorimetry
CHEM 366 II-1 Adiabatic Bomb Calorimetry Introduction Obtaining energy in the form of heat from the combustion or oxidation of thermodynamically unstable (and often kinetically inert) hydrocarbons and
More informationStandard Free Energies of Formation at 298 K. Average Bond Dissociation Energies at 298 K
1 Thermodynamics There always seems to be at least one free response question that involves thermodynamics. These types of question also show up in the multiple choice questions. G, S, and H. Know what
More informationReview and apply Investigation 5. Let s review Pages 311-312
Review and apply Investigation 5 Let s review Pages 311-312 1. After you tested all the known powders with all the test liquids, describe what you did to identify the unknown powder. Students should have
More informationQ1. A student studied the reaction between dilute hydrochloric acid and an excess of calcium carbonate.
Q. A student studied the reaction between dilute hydrochloric acid and an excess of calcium carbonate. calcium carbonate + hydrochloric acid calcium chloride + water + carbon dioxide The student measured
More informationEnthalpy of Reaction and Calorimetry worksheet
Enthalpy of Reaction and Calorimetry worksheet 1. Calcium carbonate decomposes at high temperature to form carbon dioxide and calcium oxide, calculate the enthalpy of reaction. CaCO 3 CO 2 + CaO 2. Carbon
More informationUnit 19 Practice. Name: Class: Date: Multiple Choice Identify the choice that best completes the statement or answers the question.
Name: Class: Date: Unit 19 Practice Multiple Choice Identify the choice that best completes the statement or answers the question. 1) The first law of thermodynamics can be given as. A) E = q + w B) =
More informationAP CHEMISTRY 2013 SCORING GUIDELINES
AP CHEMISTRY 2013 SCORING GUIDELINES Question 4 (15 points) For each of the following three reactions, write a balanced equation for the reaction in part (i) and answer the question about the reaction
More informationBLOWING UP BALLOONS, chemically
BLOWING UP BALLOONS, chemically PRE LAB DISCUSSION: Today we will be using a closed system. A closed system does not permit matter to enter or exit the apparatus. Lavoisier's classic 12-day experiment,
More informationChemistry 12 Worksheet 1-1 - Measuring Reaction Rates
Chemistry 12 Worksheet 1-1 - Measuring Reaction Rates 1. A chemist wishes to determine the rate of reaction of zinc with hydrochloric acid. The equation for the reaction is: Zn (s) + 2HCl (aq) oh 2(g)
More information20.2 Chemical Equations
All of the chemical changes you observed in the last Investigation were the result of chemical reactions. A chemical reaction involves a rearrangement of atoms in one or more reactants to form one or more
More informationReaction of Magnesium with Hydrochloric Acid (Gas Laws) Chemicals Needed:
Reaction of Magnesium with Hydrochloric Acid (Gas Laws) Your Name: Date: Partner(s) Names: Objectives: React magnesium metal with hydrochloric acid, collecting the hydrogen over water. Calculate the grams
More informationTest Review # 9. Chemistry R: Form TR9.13A
Chemistry R: Form TR9.13A TEST 9 REVIEW Name Date Period Test Review # 9 Collision theory. In order for a reaction to occur, particles of the reactant must collide. Not all collisions cause reactions.
More informationCHEM 105 HOUR EXAM III 28-OCT-99. = -163 kj/mole determine H f 0 for Ni(CO) 4 (g) = -260 kj/mole determine H f 0 for Cr(CO) 6 (g)
CHEM 15 HOUR EXAM III 28-OCT-99 NAME (please print) 1. a. given: Ni (s) + 4 CO (g) = Ni(CO) 4 (g) H Rxn = -163 k/mole determine H f for Ni(CO) 4 (g) b. given: Cr (s) + 6 CO (g) = Cr(CO) 6 (g) H Rxn = -26
More informationWhere the exp subscripts refer to the experimental temperature and pressure acquired in the laboratory.
Molar Volume of Carbon Dioxide Reading assignment: Julia Burdge, Chemistry 3rd edition, Chapter 10. Goals To determine the molar volume of carbon dioxide gas and the amount of sodium carbonate in a sample.
More information87 16 70 20 58 24 44 32 35 40 29 48 (a) graph Y versus X (b) graph Y versus 1/X
HOMEWORK 5A Barometer; Boyle s Law 1. The pressure of the first two gases below is determined with a manometer that is filled with mercury (density = 13.6 g/ml). The pressure of the last two gases below
More informationDetermination of the enthalpy of combustion using a bomb calorimeter TEC. Safety precautions
Safety precautions Naphthalene is harmful if swallowed. May cause cancer. Is further very toxic to aquatic organisms and can have long-term harmful effects in bodies of water. Equipment 1 Bomb calorimeter
More informationStoichiometry. Lecture Examples Answer Key
Stoichiometry Lecture Examples Answer Key Ex. 1 Balance the following chemical equations: 3 NaBr + 1 H 3 PO 4 3 HBr + 1 Na 3 PO 4 2 C 3 H 5 N 3 O 9 6 CO 2 + 3 N 2 + 5 H 2 O + 9 O 2 2 Ca(OH) 2 + 2 SO 2
More informationChapter 3! Stoichiometry: Calculations with Chemical Formulas and Equations. Stoichiometry
Chapter 3! : Calculations with Chemical Formulas and Equations Anatomy of a Chemical Equation CH 4 (g) + 2O 2 (g) CO 2 (g) + 2 H 2 O (g) Anatomy of a Chemical Equation CH 4 (g) + 2 O 2 (g) CO 2 (g) + 2
More informationTopic 4 National Chemistry Summary Notes. Formulae, Equations, Balancing Equations and The Mole
Topic 4 National Chemistry Summary Notes Formulae, Equations, Balancing Equations and The Mole LI 1 The chemical formula of a covalent molecular compound tells us the number of atoms of each element present
More informationChemistry 151 Final Exam
Chemistry 151 Final Exam Name: SSN: Exam Rules & Guidelines Show your work. No credit will be given for an answer unless your work is shown. Indicate your answer with a box or a circle. All paperwork must
More information2. The percent yield is the maximum amount of product that can be produced from the given amount of limiting reactant.
UNIT 6 stoichiometry practice test True/False Indicate whether the statement is true or false. moles F 1. The mole ratio is a comparison of how many grams of one substance are required to participate in
More informationCHEMICAL FORMULAS AND EQUATIONS
reflect Imagine that you and three other classmates had enough supplies and the recipe to make one pepperoni pizza. The recipe might include a ball of dough, a cup of pizza sauce, a cup of cheese, and
More informationReturn to Lab Menu. Stoichiometry Exploring the Reaction between Baking Soda and Vinegar
Return to Lab Menu Stoichiometry Exploring the Reaction between Baking Soda and Vinegar Objectives -to observe and measure mass loss in a gas forming reaction -to calculate CO 2 loss and correlate to a
More informationRecovery of Elemental Copper from Copper (II) Nitrate
Recovery of Elemental Copper from Copper (II) Nitrate Objectives: Challenge: Students should be able to - recognize evidence(s) of a chemical change - convert word equations into formula equations - perform
More informationFinal Exam Review. I normalize your final exam score out of 70 to a score out of 150. This score out of 150 is included in your final course total.
Final Exam Review Information Your ACS standardized final exam is a comprehensive, 70 question multiple choice (a d) test featuring material from BOTH the CHM 101 and 102 syllabi. Questions are graded
More informationMOLES AND MOLE CALCULATIONS
35 MOLES ND MOLE CLCULTIONS INTRODUCTION The purpose of this section is to present some methods for calculating both how much of each reactant is used in a chemical reaction, and how much of each product
More informationStoichiometry Limiting Reagent Laboratory. Chemistry 118 Laboratory University of Massachusetts, Boston
Chemistry 118 Laboratory University of Massachusetts, Boston STOICHIOMETRY - LIMITING REAGENT -----------------------------------------------------------------------------------------------------------------------------
More informationExperiment 3 Limiting Reactants
3-1 Experiment 3 Limiting Reactants Introduction: Most chemical reactions require two or more reactants. Typically, one of the reactants is used up before the other, at which time the reaction stops. The
More informationDetermination of the Empirical Formula of Magnesium Oxide
Determination of the Empirical Formula of Magnesium Oxide GOAL AND OVERVIEW The quantitative stoichiometric relationships governing mass and amount will be studied using the combustion reaction of magnesium
More informationEnthalpy of Combustion via Calorimetry
Enthalpy of Combustion via Calorimetry Introduction This experiment measures the enthalpy change when a system consisting of a known amount of a substance in the presence of excess oxygen is quantitatively
More informationExperiment 8: Chemical Moles: Converting Baking Soda to Table Salt
Experiment 8: Chemical Moles: Converting Baking Soda to Table Salt What is the purpose of this lab? We want to develop a model that shows in a simple way the relationship between the amounts of reactants
More informationInstructions Answer all questions in the spaces provided. Do all rough work in this book. Cross through any work you do not want to be marked.
GCSE CHEMISTRY Higher Tier Chemistry 1H H Specimen 2018 Time allowed: 1 hour 45 minutes Materials For this paper you must have: a ruler a calculator the periodic table (enclosed). Instructions Answer all
More informationSTATE UNIVERSITY OF NEW YORK COLLEGE OF TECHNOLOGY CANTON, NEW YORK COURSE OUTLINE CHEM 150 - COLLEGE CHEMISTRY I
STATE UNIVERSITY OF NEW YORK COLLEGE OF TECHNOLOGY CANTON, NEW YORK COURSE OUTLINE CHEM 150 - COLLEGE CHEMISTRY I PREPARED BY: NICOLE HELDT SCHOOL OF SCIENCE, HEALTH, AND PROFESSIONAL STUDIES SCIENCE DEPARTMENT
More informationChem 1A Exam 2 Review Problems
Chem 1A Exam 2 Review Problems 1. At 0.967 atm, the height of mercury in a barometer is 0.735 m. If the mercury were replaced with water, what height of water (in meters) would be supported at this pressure?
More informationMEMORANDUM GRADE 11. PHYSICAL SCIENCES: CHEMISTRY Paper 2
MEMORANDUM GRADE 11 PHYSICAL SCIENCES: CHEMISTRY Paper 2 MARKS: 150 TIME: 3 hours Learning Outcomes and Assessment Standards LO1 LO2 LO3 AS 11.1.1: Plan and conduct a scientific investigation to collect
More informationMr. Bracken. Multiple Choice Review: Thermochemistry
Mr. Bracken AP Chemistry Name Period Multiple Choice Review: Thermochemistry 1. If this has a negative value for a process, then the process occurs spontaneously. 2. This is a measure of how the disorder
More informationUnit 3 Notepack Chapter 7 Chemical Quantities Qualifier for Test
Unit 3 Notepack Chapter 7 Chemical Quantities Qualifier for Test NAME Section 7.1 The Mole: A Measurement of Matter A. What is a mole? 1. Chemistry is a quantitative science. What does this term mean?
More informationChem 1100 Chapter Three Study Guide Answers Outline I. Molar Mass and Moles A. Calculations of Molar Masses
Chem 1100 Chapter Three Study Guide Answers Outline I. Molar Mass and Moles A. Calculations of Molar Masses B. Calculations of moles C. Calculations of number of atoms from moles/molar masses 1. Avagadro
More informationLimiting Reagent Worksheet #1
Limiting Reagent Worksheet #1 1. Given the following reaction: (Balance the equation first!) C 3 H 8 + O 2 -------> CO 2 + H 2 O a) If you start with 14.8 g of C 3 H 8 and 3.44 g of O 2, determine the
More informationCHEMICAL REACTIONS AND REACTING MASSES AND VOLUMES
CHEMICAL REACTIONS AND REACTING MASSES AND VOLUMES The meaning of stoichiometric coefficients: 2 H 2 (g) + O 2 (g) 2 H 2 O(l) number of reacting particles 2 molecules of hydrogen react with 1 molecule
More informationChemical Equations & Stoichiometry
Chemical Equations & Stoichiometry Chapter Goals Balance equations for simple chemical reactions. Perform stoichiometry calculations using balanced chemical equations. Understand the meaning of the term
More informationExperiment 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 informationAS1 MOLES. oxygen molecules have the formula O 2 the relative mass will be 2 x 16 = 32 so the molar mass will be 32g mol -1
Moles 1 MOLES The mole the standard unit of amount of a substance the number of particles in a mole is known as Avogadro s constant (L) Avogadro s constant has a value of 6.023 x 10 23 mol -1. Example
More informationPhysical Properties of a Pure Substance, Water
Physical Properties of a Pure Substance, Water The chemical and physical properties of a substance characterize it as a unique substance, and the determination of these properties can often allow one to
More informationATOMS. Multiple Choice Questions
Chapter 3 ATOMS AND MOLECULES Multiple Choice Questions 1. Which of the following correctly represents 360 g of water? (i) 2 moles of H 2 0 (ii) 20 moles of water (iii) 6.022 10 23 molecules of water (iv)
More informationMole Notes.notebook. October 29, 2014
1 2 How do chemists count atoms/formula units/molecules? How do we go from the atomic scale to the scale of everyday measurements (macroscopic scale)? The gateway is the mole! But before we get to the
More informationExperiment 7: Titration of an Antacid
1 Experiment 7: Titration of an Antacid Objective: In this experiment, you will standardize a solution of base using the analytical technique known as titration. Using this standardized solution, you will
More informationChemistry 112 Laboratory Experiment 6: The Reaction of Aluminum and Zinc with Hydrochloric Acid
Chemistry 112 Laboratory Experiment 6: The Reaction of Aluminum and Zinc with Hydrochloric Acid Introduction Many metals react with acids to form hydrogen gas. In this experiment, you will use the reactions
More informationBalancing Chemical Equations
Why? Balancing Chemical Equations Atoms are neither created nor destroyed in a chemical reaction, they are just rearranged. In other words, in a chemical reaction, what goes into the reaction must come
More informationCP Chemistry Review for Stoichiometry Test
CP Chemistry Review for Stoichiometry Test Stoichiometry Problems (one given reactant): 1. Make sure you have a balanced chemical equation 2. Convert to moles of the known substance. (Use the periodic
More informationChapter Test B. Chapter: Measurements and Calculations
Assessment Chapter Test B Chapter: Measurements and Calculations PART I In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question. 1.
More informationUnit 2: Quantities in Chemistry
Mass, Moles, & Molar Mass Relative quantities of isotopes in a natural occurring element (%) E.g. Carbon has 2 isotopes C-12 and C-13. Of Carbon s two isotopes, there is 98.9% C-12 and 11.1% C-13. Find
More information