Chemical Reactions, Counting Atoms, and Balancing Chemical Equations.
|
|
|
- Alfred McLaughlin
- 7 years ago
- Views:
Transcription
1 Chemical Reactions, Counting Atoms, and Balancing Chemical Equations.
2 A Chemical Reaction is A process where one or more elements or compounds are changed into one or more different substances A process where the original substance changes into a new substance with new properties But, are new atoms created? Are other atoms destroyed?
3 Law of Conservation of Mass states that Matter is never created or destroyed Therefore, the mass and types of atoms that make up the reactants must be equal to the mass and types of atoms in the products. The atoms are simply rearranged.
4 Reactants and Products Reactant: the original substance (s) Product: the new substance (s) In the chemical equation, A + B AB, the reactants are A and B, which are on the left side of the equation. The product is AB and is found on the right side of the equation. The arrow in the equation means yields, or produces.
5 How Do We Know If It Is A Chemical Reaction? The following observations provide evidence that a chemical reaction is taking place: The temperature changes A gas is produced (bubbling) A precipitate forms (a solid forms from the combination of two solutions and separates out) A permanent change in color Be aware: Some physical changes produce some of the above observations. For example, food coloring in water and boiling water may look like chemical changes, but are physical changes.
6 A Chemical Reaction Adding HCl (hydrochloric acid) to zinc metal will produce bubbling and a temperature increase, two indications that a chemical change has taken place. The atoms are simply rearranged during the reaction.
7 Chemical Equation A chemical equation, or formula equation, represents what happens in a chemical reaction. For instance: The formula equation for the addition of zinc metal and hydrochloric acid looks like this: 2HCl + Zn H 2 + ZnCl 2 The arrow means yields or produces.
8 Counting Atoms in Formulas Before you can correctly write and balance an equation, you must be able to correctly count atoms in chemical formulas. Let s learn some basics
9 Know Your Equation Terms Coefficient a whole number in front of the formula that represents the relative number of moles of the substance Subscript the small number to the lower right of an atom that represents the number of atoms of that element in the molecule Coefficient of 2 means there are 2 moles of water 2H 2 O Subscript of 2 means there are 2 hydrogen atoms in a molecule of water
10 Counting Atoms in Formulas How many atoms are in this formula? CO 2 The subscript 2 belongs to the oxygen only and does not affect the carbon atom. 3 atoms in this formula 1 mole of CO 2 1 atom of carbon 2 atoms of oxygen
11 Counting Atoms in Formulas How many atoms are in this formula? 3 moles of CH 4 3CH 4 1 atom of carbon and 4 atoms of hydrogen per molecule 15 atoms in this formula
12 Counting Atoms in Formulas How many atoms are in this formula? Al(OH) 3 (OH) 3 means there are three molecules of OH bonded to the atom of aluminum. OH is in parentheses because the oxygen and hydrogen atoms are a pair. 1 mole of Al(OH) 3 There are 7 atoms in this formula.
13 Counting Atoms in Formulas How many atoms are in this formula? 2Cr 2 (CO 3 ) 3 (CO 3 ) 3 means there are three molecules of CO 3 bonded to two atoms of chromium. Count carefully! 2 moles of 2Cr 2 (CO 3 ) 3 There are 28 atoms in this formula.
14 How To Balance Chemical Equations Now that we know how to count atoms in formulas, we can begin to balance equations. Let s look at a balanced equation.
15 Chemical Equations 2HCl + Zn H 2 + ZnCl 2 The chemical equation above is a balanced equation. The reactants are: HCl and Zn The products are: H 2 and ZnCl 2 There are equal numbers and kinds of atoms in the reactants as there are in the products.
16 Chemical Equations A well-written chemical equation must: Represent a real situation the actual reactants must be able to react and form the products given Contain correct formulas for the reactants and products Abide by the Law of Conservation of Mass, which means that atoms are never created nor destroyed during chemical reactions
17 Chemical Equations Balancing chemical equations is easy if you follow some rules. You can only add a coefficient in front of a chemical formula 2H 2 O You cannot change any subscripts, nor add any subscripts O 2 You may not place a coefficient in the middle of a chemical formula Ca2Cl You must end up with the same number and kinds of atoms on both sides of the equation when you are finished. Count atoms on both sides upon completion to check yourself. 2AB 2 A 2 + 4B
18 Let s Try To Balance An Equation The word equation is: Hydrogen gas + chlorine gas hydrogen chloride The formula, or chemical equation is: H 2 + Cl 2 HCl The above equation does not satisfy the requirements of a balanced equation. Let s balance it.
19 Balance the Equation H 2 + Cl 2 HCl Begin by counting atoms on both sides H - 2 Cl - 2 H - 1 Cl - 1 It will help if you divide the two sides with a line below the arrow and list the atoms. of the arrow. Remember that the number and kinds of atoms in the reactants has to equal the numbers and kinds of atoms in the products.
20 Balance the Equation H 2 + Cl 2 2 HCl You can see that it H - 2 Cl - 2 H H Cl Cl Let s add the coefficient 2 in front of the HCl. Now let s adjust our atom totals below the equation and check. appears as if a hydrogen and an oxygen atom were lost in this reaction. That violates the Law of Conservation of Mass, so we must balance the equation by adding coefficients where necessary.
21 Balanced! H 2 + Cl 2 2HCl Now we have a balanced equation H - 2 Cl - 2 H - 2 Cl - 2 that satisfies the Law of Conservation of Mass.
22 Balance This Equation Here s another example: Al + O 2 Al 2 O 3 Al 1 Al 2 O 2 O 3 Count the number of atoms and list them under the equation. Compare each side. You might try adding a coefficient of 2 in front of the Al to balance the aluminum atoms. 2Al + O 2 Al 2 O 3 Al 2 Al 2 O 2 O - 3 It s OK if the first coefficient you try does not balance the equation.
23 Balance This Equation 2Al + 3 O 2 2 Al 2 O 3 Al 2 Al 2 O 2 O - 3 How should we fix the number of oxygen atoms? Adjust the numbers of atoms below the equation. Add a coefficient of 3 in front of the O 2 on the left, and a coefficient of 2 in front of the Al 2 O 3 on the right.
24 Balance This Equation 2Al + 3 O 2 2 Al 2 O 3 Al 2 Al 4 O 6 O - 6 How should we fix the number of oxygen atoms? Adjust the numbers of atoms below the equation. Add a coefficient of 3 in front of the O 2 on the left, and a coefficient of 2 in front of the Al 2 O 3 on the right.
25 Balance This Equation 2Al + 3O 2 2Al 2 O 3 Al 2 Al 4 O 6 O - 6 Now we still have a problem. The number of aluminum atoms do not match. Remove the 2 in front of the Al, and add a coefficient of 4. Adjust the numbers of atoms.
26 Balanced! 4Al + 3O 2 2Al 2 O 3 Al 4 Al 4 O 6 O - 6 Now we have a balanced equation!
27 Practice 1. Which of the following are balanced equations? a. NaCl Na + Cl 2 b. 2H 2 O 2H 2 + O 2 c. 2Fe(OH) 3 + 3H 2 SO 4 Fe 2 (SO 4 ) 3 + 6H 2 O d. 4NH 3 + 3O 2 2N 2 + 4H 2 O
28 Practice Balance the following equation: CO 2 + H 2 O C 6 H 12 O 6 + O 2
29 Practice Answers 1. Which of the following are balanced equations? a. NaCl Na + Cl 2 b. 2H 2 O 2H 2 + O 2 c. 2Fe(OH) 3 + 3H 2 SO 4 Fe 2 (SO 4 ) 3 + 6H 2 O d. 4NH 3 + 3O 2 2N 2 + 4H 2 O
30 Practice Answers Balance the following equation: CO 2 + H 2 O C 6 H 12 O 6 + O 2 C 1 C 6 O 3 O 8 H 2 H 12 Start by adding a coefficient of 6 in front of the CO 2 and recount the atoms; add a coefficient of 6 in front of the H 2 O and recount; finish by adding a 6 in front of the O 2 and check. 6CO 2 + 6H 2 O C 6 H 12 O 6 + 6O 2
7-5.5. 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
20.2 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
Name: Teacher: Pd. Date:
Name: Teacher: Pd. Date: STAAR Tutorial : Energy and Matter: Elements, Compounds, and Chemical Equations: 6.5C Differentiate between elements and compounds on the most basic level. 8.5F Recognize whether
Word Equations and Balancing Equations. Video Notes
Word Equations and Balancing Equations Video Notes In this lesson, you will: Use the law of conservation of mass and provide standard rules for writing and balancing equations. Write and balance equations
CHEMICAL 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
YIELD YIELD REACTANTS PRODUCTS
Balancing Chemical Equations A Chemical Equation: is a representation of a chemical reaction in terms of chemical formulas Example: 1. Word Description of a Chemical Reaction When methane gas (CH 4 ) burns
Stoichiometry Review
Stoichiometry Review There are 20 problems in this review set. Answers, including problem set-up, can be found in the second half of this document. 1. N 2 (g) + 3H 2 (g) --------> 2NH 3 (g) a. nitrogen
Balancing Chemical Equations
Balancing Chemical Equations Academic Success Center Science Tutoring Area Science Tutoring Area Law of Conservation of Mass Matter cannot be created nor destroyed Therefore the number of each type of
Answers and Solutions to Text Problems
Chapter 7 Answers and Solutions 7 Answers and Solutions to Text Problems 7.1 A mole is the amount of a substance that contains 6.02 x 10 23 items. For example, one mole of water contains 6.02 10 23 molecules
Writing and Balancing Chemical Equations
Name Writing and Balancing Chemical Equations Period When a substance undergoes a chemical reaction, chemical bonds are broken and new bonds are formed. This results in one or more new substances, often
Chapter 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
Chemical 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
Chemical Reactions 2 The Chemical Equation
Chemical Reactions 2 The Chemical Equation INFORMATION Chemical equations are symbolic devices used to represent actual chemical reactions. The left side of the equation, called the reactants, is separated
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
Chapter 8: Chemical Equations and Reactions
Chapter 8: Chemical Equations and Reactions I. Describing Chemical Reactions A. A chemical reaction is the process by which one or more substances are changed into one or more different substances. A chemical
Chapter 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
Chemical 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
Chemistry 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
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
Chemistry Diagnostic Questions
Chemistry Diagnostic Questions Answer these 40 multiple choice questions and then check your answers, located at the end of this document. If you correctly answered less than 25 questions, you need to
1. 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
Chemistry 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)
IB 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
SCH 4C1 Unit 2 Problem Set Questions taken from Frank Mustoe et all, "Chemistry 11", McGraw-Hill Ryerson, 2001
SCH 4C1 Unit 2 Problem Set Questions taken from Frank Mustoe et all, "Chemistry 11", McGraw-Hill Ryerson, 2001 1. A small pin contains 0.0178 mol of iron. How many atoms of iron are in the pin? 2. A sample
Balancing chemical equations
Balancing chemical equations The law of conservation of mass In order to balance a chemical equation, it is important to understand the law of conservation of mass. Definition 1: The law of conservation
Chemical Formulas, Equations, and Reactions Test Pre-AP Write all answers on your answer document.
Name: Period: Chemical Formulas, Equations, and Reactions Test Pre-AP Write all answers on your answer document. 1. Which of the following is a NOT a physical property of hydrogen? A. It is gas C. It is
1. How many hydrogen atoms are in 1.00 g of hydrogen?
MOLES AND CALCULATIONS USING THE MOLE CONCEPT INTRODUCTORY TERMS A. What is an amu? 1.66 x 10-24 g B. We need a conversion to the macroscopic world. 1. How many hydrogen atoms are in 1.00 g of hydrogen?
Chem 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
Chemical Equations and Chemical Reactions. Chapter 8.1
Chemical Equations and Chemical Reactions Chapter 8.1 Objectives List observations that suggest that a chemical reaction has taken place List the requirements for a correctly written chemical equation.
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
CHEMICAL REACTIONS. Chemistry 51 Chapter 6
CHEMICAL REACTIONS A chemical reaction is a rearrangement of atoms in which some of the original bonds are broken and new bonds are formed to give different chemical structures. In a chemical reaction,
How 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
11-1 Stoichiometry. Represents
11-1 Stoichiometry What is stoichiometry? Calculations that relate the quantities of substances. It is the study of quantitative (measurable amounts) relationships in chemical reactions and equations.
Steps for balancing a chemical equation
The Chemical Equation: A Chemical Recipe Dr. Gergens - SD Mesa College A. Learn the meaning of these arrows. B. The chemical equation is the shorthand notation for a chemical reaction. A chemical equation
Chem 31 Fall 2002. Chapter 3. Stoichiometry: Calculations with Chemical Formulas and Equations. Writing and Balancing Chemical Equations
Chem 31 Fall 2002 Chapter 3 Stoichiometry: Calculations with Chemical Formulas and Equations Writing and Balancing Chemical Equations 1. Write Equation in Words -you cannot write an equation unless you
Chapter 5. Chemical Reactions and Equations. Introduction. Chapter 5 Topics. 5.1 What is a Chemical Reaction
Introduction Chapter 5 Chemical Reactions and Equations Chemical reactions occur all around us. How do we make sense of these changes? What patterns can we find? 1 2 Copyright The McGraw-Hill Companies,
PART I: MULTIPLE CHOICE (30 multiple choice questions. Each multiple choice question is worth 2 points)
CHEMISTRY 123-07 Midterm #1 Answer key October 14, 2010 Statistics: Average: 74 p (74%); Highest: 97 p (95%); Lowest: 33 p (33%) Number of students performing at or above average: 67 (57%) Number of students
Instructions 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
Chapter 6 Notes Science 10 Name:
6.1 Types of Chemical Reactions a) Synthesis (A + B AB) Synthesis reactions are also known as reactions. When this occurs two or more reactants (usually elements) join to form a. A + B AB, where A and
Chapter 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
Chemical 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
Chemical Equations. Chemical Equations. Chemical reactions describe processes involving chemical change
Chemical Reactions Chemical Equations Chemical reactions describe processes involving chemical change The chemical change involves rearranging matter Converting one or more pure substances into new pure
NET IONIC EQUATIONS. A balanced chemical equation can describe all chemical reactions, an example of such an equation is:
NET IONIC EQUATIONS A balanced chemical equation can describe all chemical reactions, an example of such an equation is: NaCl + AgNO 3 AgCl + NaNO 3 In this case, the simple formulas of the various reactants
Moles. Moles. Moles. Moles. Balancing Eqns. Balancing. Balancing Eqns. Symbols Yields or Produces. Like a recipe:
Like a recipe: Balancing Eqns Reactants Products 2H 2 (g) + O 2 (g) 2H 2 O(l) coefficients subscripts Balancing Eqns Balancing Symbols (s) (l) (aq) (g) or Yields or Produces solid liquid (pure liquid)
Unit 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
Formulae, stoichiometry and the mole concept
3 Formulae, stoichiometry and the mole concept Content 3.1 Symbols, Formulae and Chemical equations 3.2 Concept of Relative Mass 3.3 Mole Concept and Stoichiometry Learning Outcomes Candidates should be
The Mole Concept and Atoms
Copyright The McGraw-Hill Companies, Inc. Permission required for reproduction or display. Chapter 4 24 September 2013 Calculations and the Chemical Equation The Mole Concept and Atoms Atoms are exceedingly
Chapter 5, Calculations and the Chemical Equation
1. How many iron atoms are present in one mole of iron? Ans. 6.02 1023 atoms 2. How many grams of sulfur are found in 0.150 mol of sulfur? [Use atomic weight: S, 32.06 amu] Ans. 4.81 g 3. How many moles
Moles. Balanced chemical equations Molar ratios Mass Composition Empirical and Molecular Mass Predicting Quantities Equations
Moles Balanced chemical equations Molar ratios Mass Composition Empirical and Molecular Mass Predicting Quantities Equations Micro World atoms & molecules Macro World grams Atomic mass is the mass of an
Other Stoich Calculations A. mole mass (mass mole) calculations. GIVEN mol A x CE mol B. PT g A CE mol A MOLE MASS :
Chem. I Notes Ch. 12, part 2 Using Moles NOTE: Vocabulary terms are in boldface and underlined. Supporting details are in italics. 1 MOLE = 6.02 x 10 23 representative particles (representative particles
Topic 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
Notes Chapter 9 Limiting Reagent Sample Problems Page 1
Notes Chapter 9 Limiting Reagent Sample Problems Page 1 Problem 1: Sodium chloride can be prepared by the reaction of sodium metal with chlorine gas. Suppose that 6.70 Na reacts with 3.20 Cl 2. A. What
Chapter 11. Electrochemistry Oxidation and Reduction Reactions. Oxidation-Reduction Reactions. Oxidation-Reduction Reactions
Oxidation-Reduction Reactions Chapter 11 Electrochemistry Oxidation and Reduction Reactions An oxidation and reduction reaction occurs in both aqueous solutions and in reactions where substances are burned
Chemical 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?
Sample Problem: STOICHIOMETRY and percent yield calculations. How much H 2 O will be formed if 454 g of. decomposes? NH 4 NO 3 N 2 O + 2 H 2 O
STOICHIOMETRY and percent yield calculations 1 Steps for solving Stoichiometric Problems 2 Step 1 Write the balanced equation for the reaction. Step 2 Identify your known and unknown quantities. Step 3
Unit 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
CHEM 110: CHAPTER 3: STOICHIOMETRY: CALCULATIONS WITH CHEMICAL FORMULAS AND EQUATIONS
1 CHEM 110: CHAPTER 3: STOICHIOMETRY: CALCULATIONS WITH CHEMICAL FORMULAS AND EQUATIONS The Chemical Equation A chemical equation concisely shows the initial (reactants) and final (products) results of
Chapter 5 Chemical Quantities and Reactions. Collection Terms. 5.1 The Mole. A Mole of a Compound. A Mole of Atoms.
Chapter 5 Chemical Quantities and Reactions 5.1 The Mole Collection Terms A collection term states a specific number of items. 1 dozen donuts = 12 donuts 1 ream of paper = 500 sheets 1 case = 24 cans 1
Writing, Balancing and Predicting Products of Chemical Reactions.
Writing, Balancing and Predicting Products of Chemical Reactions. A chemical equation is a concise shorthand expression which represents the relative amount of reactants and products involved in a chemical
Balancing 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
Chemistry Post-Enrolment Worksheet
Name: Chemistry Post-Enrolment Worksheet The purpose of this worksheet is to get you to recap some of the fundamental concepts that you studied at GCSE and introduce some of the concepts that will be part
Chapter 3 Stoichiometry
Chapter 3 Stoichiometry 3-1 Chapter 3 Stoichiometry In This Chapter As you have learned in previous chapters, much of chemistry involves using macroscopic measurements to deduce what happens between atoms
Stoichiometry. Unit Outline
3 Stoichiometry Unit Outline 3.1 The Mole and Molar Mass 3.2 Stoichiometry and Compound Formulas 3.3 Stoichiometry and Chemical Reactions 3.4 Stoichiometry and Limiting Reactants 3.5 Chemical Analysis
Stoichiometry. What is the atomic mass for carbon? For zinc?
Stoichiometry Atomic Mass (atomic weight) Atoms are so small, it is difficult to discuss how much they weigh in grams We use atomic mass units an atomic mass unit (AMU) is one twelfth the mass of the catbon-12
Lecture 5, The Mole. What is a mole?
Lecture 5, The Mole What is a mole? Moles Atomic mass unit and the mole amu definition: 12 C = 12 amu. The atomic mass unit is defined this way. 1 amu = 1.6605 x 10-24 g How many 12 C atoms weigh 12 g?
Balance the following equation: KClO 3 + C 12 H 22 O 11 KCl + CO 2 + H 2 O
Balance the following equation: KClO 3 + C 12 H 22 O 11 KCl + CO 2 + H 2 O Ans: 8 KClO 3 + C 12 H 22 O 11 8 KCl + 12 CO 2 + 11 H 2 O 3.2 Chemical Symbols at Different levels Chemical symbols represent
Unit 10A Stoichiometry Notes
Unit 10A Stoichiometry Notes Stoichiometry is a big word for a process that chemist s use to calculate amounts in reactions. It makes use of the coefficient ratio set up by balanced reaction equations
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
Stoichiometry. 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
Chemistry Final Study Guide
Name: Class: Date: Chemistry Final Study Guide Multiple Choice Identify the choice that best completes the statement or answers the question. 1. The electrons involved in the formation of a covalent bond
Name Date Class STOICHIOMETRY. SECTION 12.1 THE ARITHMETIC OF EQUATIONS (pages 353 358)
Name Date Class 1 STOICHIOMETRY SECTION 1.1 THE ARITHMETIC OF EQUATIONS (pages 353 358) This section explains how to calculate the amount of reactants required or product formed in a nonchemical process.
CHEM 120 Online: Chapter 6 Sample problems Date: 2. Which of the following compounds has the largest formula mass? A) H2O B) NH3 C) CO D) BeH2
CHEM 120 Online: Chapter 6 Sample problems Date: 1. To determine the formula mass of a compound you should A) add up the atomic masses of all the atoms present. B) add up the atomic masses of all the atoms
Target Mole Lab. Mole Relationships and the Balanced Equation. For each student group Hydrochloric acid solution, HCl, 3 M, 30 ml
elearning 2009 Introduction Target Mole Lab Mole Relationships and the Balanced Equation Publication No. A common chemical reaction used in chemistry class is zinc and hydrochloric In this lab, students
stoichiometry = the numerical relationships between chemical amounts in a reaction.
1 REACTIONS AND YIELD ANSWERS stoichiometry = the numerical relationships between chemical amounts in a reaction. 2C 8 H 18 (l) + 25O 2 16CO 2 (g) + 18H 2 O(g) From the equation, 16 moles of CO 2 (a greenhouse
Balancing Chemical Equations Practice
Science Objectives Students will describe what reactants and products in a chemical equation mean. Students will explain the difference between coefficients and subscripts in chemical equations. Students
AP 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
CONSERVATION OF MASS During a chemical reaction, matter is neither created nor destroyed. - i. e. the number of atoms of each element remains constant
1 CHEMICAL REACTINS Example: Hydrogen + xygen Water H + H + + - Note there is not enough hydrogen to react with oxygen - It is necessary to balance equation. reactants products + H + H (balanced equation)
1. When the following equation is balanced, the coefficient of Al is. Al (s) + H 2 O (l)? Al(OH) 3 (s) + H 2 (g)
1. When the following equation is balanced, the coefficient of Al is. Al (s) + H 2 O (l)? Al(OH) (s) + H 2 (g) A) 1 B) 2 C) 4 D) 5 E) Al (s) + H 2 O (l)? Al(OH) (s) + H 2 (g) Al (s) + H 2 O (l)? Al(OH)
Chapter Three: STOICHIOMETRY
p70 Chapter Three: STOICHIOMETRY Contents p76 Stoichiometry - The study of quantities of materials consumed and produced in chemical reactions. p70 3-1 Counting by Weighing 3-2 Atomic Masses p78 Mass Mass
neutrons are present?
AP Chem Summer Assignment Worksheet #1 Atomic Structure 1. a) For the ion 39 K +, state how many electrons, how many protons, and how many 19 neutrons are present? b) Which of these particles has the smallest
Chapter 3 Mass Relationships in Chemical Reactions
Chapter 3 Mass Relationships in Chemical Reactions Student: 1. An atom of bromine has a mass about four times greater than that of an atom of neon. Which choice makes the correct comparison of the relative
Chemical Reactions in Water Ron Robertson
Chemical Reactions in Water Ron Robertson r2 f:\files\courses\1110-20\2010 possible slides for web\waterchemtrans.doc Properties of Compounds in Water Electrolytes and nonelectrolytes Water soluble compounds
Chemical Calculations
Moles and Molecules Moles and Chemical Reactions Moles, Chemical Reactions, and Molarity All done as UNIT CONVERSIONS!!! and practice, practice, practice CHM 1010 Sinex 1 Mass moles particles conversions
Balancing Chemical Equations Worksheet
Balancing Chemical Equations Worksheet Student Instructions 1. Identify the reactants and products and write a word equation. 2. Write the correct chemical formula for each of the reactants and the products.
U3-LM2B-WS Molar Mass and Conversions
U3-LM2B-WS Molar Mass and Conversions Name: KEY 1. The molar mass of chlorine is: 2 x 35.45 g/mol Cl = 70.90 g/mol Cl 2 (Remember that chlorine exists as a diatomic molecule in nature) 2. The molar mass
Experiment 5. Chemical Reactions A + X AX AX A + X A + BX AX + B AZ + BX AX + BZ
Experiment 5 Chemical Reactions OBJECTIVES 1. To observe the various criteria that are used to indicate that a chemical reaction has occurred. 2. To convert word equations into balanced inorganic chemical
Experiment 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
MOLES 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
Unit 9 Stoichiometry Notes (The Mole Continues)
Unit 9 Stoichiometry Notes (The Mole Continues) is a big word for a process that chemist s use to calculate amounts in reactions. It makes use of the coefficient ratio set up by balanced reaction equations
English already has many collective nouns for fixed, given numbers of objects. Some of the more common collective nouns are shown in Table 7.1.
96 Chapter 7: Calculations with Chemical Formulas and Chemical Reactions Chemical reactions are written showing a few individual atoms or molecules reacting to form a few atoms or molecules of products.
Formulas, Equations and Moles
Chapter 3 Formulas, Equations and Moles Interpreting Chemical Equations You can interpret a balanced chemical equation in many ways. On a microscopic level, two molecules of H 2 react with one molecule
Chemistry 65 Chapter 6 THE MOLE CONCEPT
THE MOLE CONCEPT Chemists find it more convenient to use mass relationships in the laboratory, while chemical reactions depend on the number of atoms present. In order to relate the mass and number of
Name Date Class CHEMICAL QUANTITIES. SECTION 10.1 THE MOLE: A MEASUREMENT OF MATTER (pages 287 296)
Name Date Class 10 CHEMICAL QUANTITIES SECTION 10.1 THE MOLE: A MEASUREMENT OF MATTER (pages 287 296) This section defines the mole and explains how the mole is used to measure matter. It also teaches
Chapter 6: Writing and Balancing Chemical Equations. AB A + B. CaCO3 CaO + CO2 A + B C. AB + C AC + B (or AB + C CB + A)
78 Chapter 6: Writing and Balancing Chemical Equations. It is convenient to classify chemical reactions into one of several general types. Some of the more common, important, reactions are shown below.
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
CP 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
Stoichiometry. 1. The total number of moles represented by 20 grams of calcium carbonate is (1) 1; (2) 2; (3) 0.1; (4) 0.2.
Stoichiometry 1 The total number of moles represented by 20 grams of calcium carbonate is (1) 1; (2) 2; (3) 01; (4) 02 2 A 44 gram sample of a hydrate was heated until the water of hydration was driven
CHEMICAL 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
Return 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
Balancing Reaction Equations Oxidation State Reduction-oxidation Reactions
Balancing Reaction Equations Oxidation State Reduction-oxidation Reactions OCN 623 Chemical Oceanography Balanced chemical reactions are the math of chemistry They show the relationship between the reactants