C2.6 Quantitative Chemistry Foundation

Size: px
Start display at page:

Download "C2.6 Quantitative Chemistry Foundation"

Transcription

1 C2.6 Quantitative Chemistry Foundation 1. Relative masses Use the periodic table to find the relative masses of the elements below. (Hint: The top number in each element box) Hydrogen Carbon Nitrogen Oxygen Sodium Magnesium Chlorine Potassium Calcium Zinc 2. Relative formula masses Use the relative masses you found out and combine them to make the relative formula masses of these substances. (Hint: The small numbers only affect the letter it is immediately behind) (Hint: Everything in a bracket is multiplied by the small number behind it) (Hint: Each new atom has a capital letter) Oxygen, O2 Water, H2O Ammonia, NH3 Carbon dioxide, CO2 Copper sulfate, CuSO4 Iron hydroxide, Fe(OH)3 Magnesium hydroxide, Mg(OH)2 Aluminium nitrate, Al(NO3)3

2 3. Empirical formula This helps you find out the ratio of atoms inside a compound. Worked example: Calcium chloride was made by reacting 10g of calcium and 17.8g of chlorine Symbol for element Ca Cl Mass in g Relative atomic mass Divide the mass of each 10 / 40 = / 35.5 = 0.5 element by its relative atomic mass Divide the answers by 0.25 / 0.25 = / 0.25 = 2 the smallest number to find the simplest ratio Empirical formula CaCl 2 Use the tables below to work out the empirical formulas for these compounds a) Sodium chloride, if a sample contains 4.6 g of sodium and 7.1 g of chlorine Symbol of element Na Cl Mass in g Relative atomic mass Divide the mass of each element by its relative atomic mass Divide the answers by the smallest number to find the simplest ratio Empirical formula b) Zinc chloride, if a sample contains 10.4 g of zinc and g of chlorine Symbol of element Zn Cl Mass in g Relative atomic mass Divide the mass of each element by its relative atomic mass Divide the answers by the smallest number to find the simplest ratio Empirical formula

3 c) Copper sulfate, if a sample contains g of copper, 9.6 g of sulfur and 19.2 g of oxygen Symbol of element Cu S O Mass in g Relative atomic mass Divide the mass of each element by its relative atomic mass Divide the answers by the smallest number to find the simplest ratio Empirical formula

4 4. Percentage by mass This tells you the percentage mass of each element in the compound. E.g. What is the percentage of oxygen in water? Worked example: What is the percentage of oxygen in potassium nitrate, KNO 3? Relative formula mass of potassium nitrate, KNO 3 K = 39, N = 14, O = (3x16) = 101 Number of atoms of oxygen in KNO 3 3 Relative atomic mass of oxygen 16 % of oxygen in KNO 3 3 x 16 x 100 = 47.5% 101 Use the tables below to complete the questions on percentage by mass a) Calculate the percentage by mass of oxygen in water, H 2 O Relative formula mass of compound Number of atoms of oxygen in the element you are looking for Relative atomic mass of the element you are looking for % of element in compound b) Calculate the percentage by mass of oxygen in carbon dioxide, CO 2 Relative formula mass of compound Number of atoms of oxygen in the element you are looking for Relative atomic mass of the element you are looking for % of element in compound c) Calculate the percentage by mass of oxygen in Calcium chloride, CaCl 2 Relative formula mass of compound Number of atoms of oxygen in the element you are looking for Relative atomic mass of the element you are looking for % of element in compound

5 5. Yield Theoretical yield is how much product you should make from your start chemicals. Actual yield is how much you actually make in a real reaction Percentage yield is how much actual yield you make compared to theoretical yield. The equation to work out percentage yield is: Percentage yield = actual yield x 100 Theoretical yield For example: In the reaction between hydrogen and oxygen the actual yield was 30g, but the theoretical yield was 36g. 30 / 36 x 100 = 83.3% Work out the percentage yields for the reactions below: Actual Yield in g Theoretical yield in g Percentage yield in % Theoretical yield worked example: (Hint: In the equation, both sides of the arrow should add up to the same mass in g) What will be the yield of water when you react hydrogen and oxygen together? Balanced equation 2H 2 O 2 2H 2 O Calculate formula masses and add g Answer: H = 1 2 x (1+1) = 4g O = 16 2 x 16 = 32g H = 1, O = 16 (2 x 2) + (2 x 16) = 36g 36g of water will be made from 4g of hydrogen and 32g of oxygen

6 Complete the questions below: Balanced equation Calculate the formula masses and add g Answer H 2 + F 2 HF + Balanced equation Calculate the formula masses and add g Answer K + Br 2 KBr +

7 1. Yield The equation to work out percentage yield is: Percentage yield = actual yield x 100 Theoretical yield Work out the percentage, theoretical or actual yields for the reactions below: a) The theoretical yield is 100 g but the actual yield was 75g b) The theoretical yield is 80g whereas the actual yield was 20g c) The actual yield as 8 g whereas the expected yield was 64g d) The percentage yield was 25 g and the theoretical yield was 50g e) The percentage yield was 80g and the theoretical yield was 40g Theoretical yield This tells you how much product you should be making from a reaction. Use p182 to find a worked example (Hint: You need to balance the equations before you work out the products) a) Iron oxide (Fe 2 O 3 ) was reacted with Carbon monoxide (CO) to make Iron (Fe) and Carbon dioxide (CO 2 ) b) Sulfur dioxide (SO 2 ) was reacted with Oxygen (O 2 ) to produce Sulphur trioxide (SO 3 ) c) Calcium carbonate (CaCO 3 ) is thermally decomposed to produce Calcium oxide (CaO) and Carbon dioxide (CO 2 ) Extension Explain the reasons why the actual yield of a reaction may be less than the theoretical yield.

8 1. Calculating a reacting mass During a chemical reaction, no atoms are lost or made, they are just rearranged to make new substances. You can use relative masses and the balanced equation for a reaction to calculate the mass of a reactant or a product. Worked example In a firework, potassium nitrate (KNO 3 ) is decomposed to potassium nitrate (KNO 2 ) and oxygen (O 2 ). What mass of potassium nitrate is needed in a firework to make 1.6g of oxygen? Write the balanced equation 2KNO 3 2KNO 2 + O 2 Work out the relative masses of the substances needed in the calculation. Notice that we need to multiply the relative masses of KNO3 by 2 because there are two particles of KNO3 in the balanced equation Convert the relative masses into the units in the question Divide the answers by the smallest number to find the ratio Find the mass of potassium nitrate needed to make 1.6 g of oxygen Answer KNO3 = 39 (K) + 14 (N) + (3x16) (O) = 101 O2 = 2x16 = 32 2 x g 32g so 202/ 32 32/32 = x x g of potassium nitrate are needed to make 1.6g of oxygen Use the worked example above to complete the questions below. a) Copper oxide can be reduced by hydrogen. What mass of copper could be obtained from 79.5g of copper oxide? CuO + H 2 Cu + H 2 O b) Calculate the mass of carbon dioxide you could obtain by adding hydrochloric acid to 15g of calcium carbonate: CacO 2 + 2HCl CaCl 2 + H 2 O + CO 2

C2.6 Quantitative Chemistry Foundation

C2.6 Quantitative Chemistry Foundation C2.6 Quantitative Chemistry Foundation 1. Relative masses Use the periodic table to find the relative masses of the elements below. (Hint: The top number in each element box) Hydrogen Carbon Nitrogen Oxygen

More information

2. Relative molecular mass, M r - The relative molecular mass of a molecule is the average mass of the one molecule when compared with

2. Relative molecular mass, M r - The relative molecular mass of a molecule is the average mass of the one molecule when compared with Chapter 3: Chemical Formulae and Equations 1. Relative atomic mass, A r - The relative atomic mass of an element is the average mass of one atom of an element when compared with mass of an atom of carbon-12

More information

NCERT Solutions for Atoms and Molecules

NCERT Solutions for Atoms and Molecules 1 NCERT Solutions for Atoms and Molecules Question 1. In a reaction, 5.3 g of sodium carbonate reacted with 6 g of ethanoic acid. The products were 2.2 g of carbon dioxide, 0.9 g water and 8.2 g of sodium

More information

Chemical reactions: Chemical reactions change substances into other substances.

Chemical reactions: Chemical reactions change substances into other substances. Chemical reactions: Chemical reactions change substances into other substances. A chemical equation is used to represent a reaction. This has the form: reactants à products Word equations use the names

More information

3. Which postulate of Dalton s atomic theory is the result of the law of conservation of mass?

3. Which postulate of Dalton s atomic theory is the result of the law of conservation of mass? 1 1. In a reaction, 5.3 g of sodium carbonate reacted with 6 g of ethanoic acid. The products were 2.2 g of carbon dioxide, 0.9 g water and 8.2 g of sodium ethanoate. Show that these observations are in

More information

Class IX Chapter 3 Atoms and Molecules Science

Class IX Chapter 3 Atoms and Molecules Science Class IX Chapter 3 Atoms and Molecules Science Question 1: In a reaction, 5.3 g of sodium carbonate reacted with 6 g of ethanoic acid. The products were 2.2 g of carbon dioxide, 0.9 g water and 8.2 g of

More information

(DO NOT WRITE ON THIS TEST)

(DO NOT WRITE ON THIS TEST) Final Prep Chap 8&9 (DO NOT WRITE ON THIS TEST) Multiple Choice Identify the choice that best completes the statement or answers the question. 1. After the correct formula for a reactant in an equation

More information

UNIT 1 Chemical Reactions Part II Workbook. Name:

UNIT 1 Chemical Reactions Part II Workbook. Name: UNIT 1 Chemical Reactions Part II Workbook Name: 1 Molar Volume 1. How many moles of a gas will occupy 2.50 L at STP? 2. Calculate the volume that 0.881 mol of gas at STP will occupy. 3. Determine the

More information

Year 12 Chemistry Transition Work - QPHS

Year 12 Chemistry Transition Work - QPHS Year 12 Chemistry Transition Work - QPHS Contents Task 1: Task 2 Task 3 Task 4 Task 5 Task 6 Task 7 Task 8 The structure of atoms Writing formulae Relative masses Balancing equations Writing symbol equations

More information

How many hydrogen atoms are there in the empirical formula of propene, C 3 H 6? How many neutrons are there in one atom of 24 Mg?

How many hydrogen atoms are there in the empirical formula of propene, C 3 H 6? How many neutrons are there in one atom of 24 Mg? 1 A 2 B 3 C The atomic number of Na is 11. How many electrons are there in a sodium ion, Na +? How many hydrogen atoms are there in the empirical formula of propene, C 3 H 6? What is the mass in grams

More information

Question 8 Chemical properties of metals and nonmetals. 1) magnesium 2) sulfur trioxide 3) iron (II) hydroxide 4) sodium nitrate

Question 8 Chemical properties of metals and nonmetals. 1) magnesium 2) sulfur trioxide 3) iron (II) hydroxide 4) sodium nitrate Question 8 Chemical properties of metals and nonmetals 1. Calcium oxide doesn t react with 1) NaNO 3 2) HCl 3) CO 2 4) H 2 O 2. Calcium oxide reacts with both of the following 1) SO 2 and O 2 2) H 2 O

More information

Chem!stry. Question 1: Which other chemical elements are diatomic? Write their names and formulae below:

Chem!stry. Question 1: Which other chemical elements are diatomic? Write their names and formulae below: Chem!stry Name: ( ) Class: Date: / / Chemical Symbols and Formulae Chemists use symbols and formulae as a concise way of describing chemical elements and compounds. The symbols of some chemical elements

More information

SCIENCE JSUNIL TUTORIAL CLASS 9. Activity 1

SCIENCE JSUNIL TUTORIAL CLASS 9. Activity 1 Activity Objective To understand, that there is a change in mass when a chemical change takes place. (To understand law of conservation of mass experimentally). Procedure. Take one of the following sets,

More information

Topic 1a Atomic Structure Revision Notes

Topic 1a Atomic Structure Revision Notes Topic 1a Atomic Structure 1) Fundamental particles Atoms consist of protons, neutrons and electrons Protons and neutrons are found in the nucleus which contains most of the mass of the atom and all of

More information

IGCSE (9-1) Edexcel - Chemistry

IGCSE (9-1) Edexcel - Chemistry IGCSE (9-1) Edexcel - Chemistry Principles of Chemistry Chemical Formulae, Equations and Calculations NOTES 1.25: Write word equations and balanced chemical equations (including state symbols): For reactions

More information

Chemical Reactions Unit

Chemical Reactions Unit Name: Hour: Teacher: ROZEMA / Chemistry Chemical Reactions Unit 1 P a g e 2 P a g e 3 P a g e 4 P a g e 5 P a g e 6 P a g e Chemistry Balancing Equations Balance the following equations by inserting the

More information

Bullers Wood School. Chemistry Department. Transition to A Level Chemistry Workbook. June 2018

Bullers Wood School. Chemistry Department. Transition to A Level Chemistry Workbook. June 2018 Bullers Wood School Chemistry Department Transition to A Level Chemistry Workbook June 2018 This booklet contains questions for you to work through and answer over the summer to prepare for the A level

More information

Chemical Reactions. Chemical changes are occurring around us all the time

Chemical Reactions. Chemical changes are occurring around us all the time Chemical changes are occurring around us all the time Food cooking Fuel being burned in a car s engine Oxygen being used in the human body The starting materials are called reactants The ending materials

More information

CHEMICAL REACTIONS. Introduction. Chemical Equations

CHEMICAL REACTIONS. Introduction. Chemical Equations CHEMICAL REACTIONS Chemistry I Chapter 7 1 Chemical Equations Their Job: Depict the kind of reactants and products and their relative amounts in a reaction. 4 Al (s) + 3 O 2 (g) ---> 2 Al 2 O 3 (s) The

More information

Symbols. Table 1 A set of common elements, their symbols and physical state

Symbols. Table 1 A set of common elements, their symbols and physical state Symbols Symbols are a kind of shorthand system for writing down elements and compounds. Each element has a particular one or two letter symbol. The first letter of a symbol is always capital, and if there

More information

5072 CHEMISTRY (NEW PAPERS WITH SPA) BASIC TECHNIQUES 5067 CHEMISTRY (NEW PAPERS WITH PRACTICAL EXAM) BASIC TECHNIQUES

5072 CHEMISTRY (NEW PAPERS WITH SPA) BASIC TECHNIQUES 5067 CHEMISTRY (NEW PAPERS WITH PRACTICAL EXAM) BASIC TECHNIQUES 5072 CHEMISTRY (NEW PAPERS WITH SPA) BASIC TECHNIQUES 5067 CHEMISTRY (NEW PAPERS WITH PRACTICAL EXAM) BASIC TECHNIQUES LEARNING OUTCOMES a) Be able to write formulae of simple compounds b) Be able to write

More information

Balancing CHEMICAL EQUATIONS

Balancing CHEMICAL EQUATIONS Balancing CHEMICAL EQUATIONS CHEMICAL REACTIONS involves a chemical change in the identity of one or more chemical species Ex. Rusting of iron (Fe): chemical rxn btwn water and iron involve the breaking

More information

Chemistry. Bridging the Gap Summer Homework. Name..

Chemistry. Bridging the Gap Summer Homework. Name.. Chemistry Bridging the Gap Summer Homework Name.. Standard Form Number Number in standard form 0.008 8 x 10-3 0.07 7 x 10-2 0.55 5.5 x 10-1 0.000052 0.048 0.0086 0.00086 0.000086 0.0000000001 0.000455

More information

Formulae and Equations

Formulae and Equations Formulae and Equations 1 of 41 Boardworks Ltd 2016 Formulae and Equations 2 of 41 Boardworks Ltd 2016 Forming different compounds 3 of 41 Boardworks Ltd 2016 Elements are made up of just one type of atom.

More information

Stoichiometry. Introduction. Rx between Hydrogen and Oxygen can be described as: Balanced equation: Or Avogadros Number: (number of Molecules)

Stoichiometry. Introduction. Rx between Hydrogen and Oxygen can be described as: Balanced equation: Or Avogadros Number: (number of Molecules) Stoichiometry Introduction Rx between Hydrogen and Oxygen can be described as: Balanced equation: Or Or Avogadros Number: (number of Molecules) Or Moles (amount of a substance containing avogadros number

More information

If Sally has 4.56 x atoms of oxygen in a sample of aluminum oxide, how many kilograms of aluminum does she have?

If Sally has 4.56 x atoms of oxygen in a sample of aluminum oxide, how many kilograms of aluminum does she have? If Sally has 4.56 x 10 34 atoms of oxygen in a sample of aluminum oxide, how many kilograms of aluminum does she have? Bertha has.025 milligrams of sodium that she got from a sample of Sodium phosphate,

More information

Chapter 9. Table of Contents. Stoichiometry. Section 1 Introduction to Stoichiometry. Section 2 Ideal Stoichiometric Calculations

Chapter 9. Table of Contents. Stoichiometry. Section 1 Introduction to Stoichiometry. Section 2 Ideal Stoichiometric Calculations Stoichiometry Table of Contents Section 1 Introduction to Stoichiometry Section 2 Ideal Stoichiometric Calculations Section 3 Limiting Reactants and Percentage Yield Section 1 Introduction to Stoichiometry

More information

REVIEW OF BASIC CHEMISTRY ANSWER KEY

REVIEW OF BASIC CHEMISTRY ANSWER KEY REVIEW OF BASIC CHEMISTRY ANSWER KEY 1. Name the following elements. Spelling counts: 2. Write the symbols for the following elements. H hydrogen sodium Na S sulphur phosphorus P Cl chlorine fluorine F

More information

Chemical Bonds In elements and compounds, the atoms are held together by chemical bonds.

Chemical Bonds In elements and compounds, the atoms are held together by chemical bonds. Chemical Bonds In elements and compounds, the atoms are held together by chemical bonds. Forming a bond makes an atom more stable, so atoms form as many bonds are they are able to. Bonds are made using

More information

Chapter-3: Atoms and Molecules

Chapter-3: Atoms and Molecules 1 Titbits: Chapter-3: Atoms and Molecules Smallest unit of any matter is called an atom Molecule is a group of atoms that are held together by a chemical bond. Compound is a form of matter formed when

More information

Chapter 5 Chemical Calculations

Chapter 5 Chemical Calculations Calculating moles Moles and elements Moles and compounds Moles and gases Moles and solutions Calculating formulae Finding the formula Chapter 5 Chemical Calculations Moles and chemical equations Checklist

More information

The Masses of chemicals

The Masses of chemicals The Masses of chemicals Boardworks Ltd 2003 WILF To give a definition of relative formula mass M r. To calculate relative formula mass if its formula and the relative atomic mass are given. To give a full

More information

Identify the reaction type, predict the products, and balance the equations. If it is a special decomposition or synthesis, identify which kind.

Identify the reaction type, predict the products, and balance the equations. If it is a special decomposition or synthesis, identify which kind. Identify the reaction type, predict the products, and balance the equations. If it is a special decomposition or synthesis, identify which kind. 1. calcium + oxygen 2. cupric carbonate 3. aluminum + hydrochloric

More information

Funsheet 3.0 [WRITING & BALANCING EQUATIONS] Gu/R. 2017

Funsheet 3.0 [WRITING & BALANCING EQUATIONS] Gu/R. 2017 Funsheet 3.0 [WRITING & BALANCING EQUATIONS] Gu/R. 2017 Balance the following chemical equations. Remember, it is not necessary to write "1" if the coefficient is one. 1. N 2 + H 2 NH 3 2. KClO 3 KCl +

More information

CHEMISTRY 135 REVISION OF NAMES, FORMULAE AND EQUATIONS

CHEMISTRY 135 REVISION OF NAMES, FORMULAE AND EQUATIONS CHEMISTRY 135 REVISION OF NAMES, FORMULAE AND EQUATIONS Answer the following questions as if you were going to hand them in for marking. You will be tested on them in class time. 1) Give the correct chemical

More information

CHEMICAL EQUATIONS WHAT BALANCING AN EQUATION MEANS

CHEMICAL EQUATIONS WHAT BALANCING AN EQUATION MEANS 17 CHEMICAL EQUATIONS WHAT BALANCING AN EQUATION MEANS WHAT IS A CHEMICAL EQUATION? A chemical equation is a way of representing a chemical reaction in symbolic form. For example, when hydrochloric acid

More information

Unit 10: Stoichiometry Funsheets. Part A: Balanced Chemical Equations- Balance the following chemical equations.

Unit 10: Stoichiometry Funsheets. Part A: Balanced Chemical Equations- Balance the following chemical equations. Unit 10: Stoichiometry Funsheets Part A: Balanced Chemical Equations- Balance the following chemical equations. 1) Al + Cl 2 AlCl 3 2) Mg(ClO) 2 MgCl 2 + O 2 3) FeCl 3 + LiOH Fe(OH) 3 + LiCl 4) Na + O

More information

A-LEVEL TRANSITION COURSE SUMMER 2018 PART 2: USING CHEMICAL EQUATIONS

A-LEVEL TRANSITION COURSE SUMMER 2018 PART 2: USING CHEMICAL EQUATIONS A-LEVEL TRANSITION COURSE SUMMER 2018 PART 2: USING CHEMICAL EQUATIONS MASS AQUEOUS VOLUME ` MOLAR MASS GASEOUS VOLUME MOLES CONCENTRATION REVISION FROM LESSON 1 How many moles? 1) Jahin weighs a sample

More information

Chemical measurements QuestionIT

Chemical measurements QuestionIT Chemical measurements QuestionIT 1. What is the law of conservation of mass? Mass of reactants = mass products. 2. Why might some reactions appear to show a change in mass? A reactant or a product is a

More information

Chem A Ch. 9 Practice Test

Chem A Ch. 9 Practice Test Name: Class: Date: Chem A Ch. 9 Practice Test Matching Match each item with the correct statement below. a. product d. balanced equation b. reactant e. skeleton equation c. chemical equation 1. a new substance

More information

Wales High School Science Department Chemistry. Name:

Wales High School Science Department Chemistry. Name: GCSE to A-level Transition Workbook Wales High School Science Department Chemistry Name: Moving from GCSE to A Level chemistry Introduction Welcome to the A-level chemistry course at Wales High School.

More information

BALANCING EQUATIONS NOTES

BALANCING EQUATIONS NOTES BALANCING EQUATIONS NOTES WHY DO WE NEED TO BALANCE CHEMICAL EQUATIONS? The LAW OF CONSERVATION OF MASS says that matter cannot be created or destroyed. In other words, you cannot end up with any more

More information

1.21. Formulae, equations and amounts of substance

1.21. Formulae, equations and amounts of substance 1.21. Formulae, equations and amounts of substance The mole is the key concept for chemical calculations DEFINITION: The mole is the amount of substance in grams that has the same number of particles as

More information

Chemical Reactions. Ch. 11 Chemical Reactions. Chemical Reactions. Chemical Reactions

Chemical Reactions. Ch. 11 Chemical Reactions. Chemical Reactions. Chemical Reactions Chemical Reactions Ch. 11 Chemical Reactions when a substance changes identity Reactants - original Products - resulting law of conservation of mass total mass of reactants = total mass of products In

More information

Unit 6: Mole Assignment Packet Period:

Unit 6: Mole Assignment Packet Period: Unit 6: Mole Assignment Packet Name: Period: A1: Mole Conversions 1. Identify the representative particle in each of the following: (atom, molecule, formula unit) a. CuSO 4 b. H 2 O c. NaCl d. Zn e. Cu

More information

SIXTH FORM AES CHEMISTRY TRANSITION UNIT. Name: Secondary School

SIXTH FORM AES CHEMISTRY TRANSITION UNIT. Name: Secondary School SIXTH FORM AES CHEMISTRY TRANSITION UNIT Name: Secondary School 0 1 Contents Introduction 2 Task 1: The structure of atoms 3 Task 2: Atoms and ions 4 Task 3: Writing formulas 5 Task 4: Relative masses

More information

Science. Reactions and compounds. Chemical reactions

Science. Reactions and compounds. Chemical reactions Science Chemical reactions When elements react, their atoms join with other atoms to form compounds [compound: A compound is a substance formed by the chemical union (involving bond formation) of two or

More information

Balancing Equations Notes

Balancing Equations Notes . Unit 6 Chemical Equations and Reactions What is a Chemical Equation? A Chemical Equation is a written representation of the process that occurs in a chemical reaction. A chemical equation is written

More information

Chemical Reactions CHAPTER Reactions and Equations

Chemical Reactions CHAPTER Reactions and Equations CHAPTER 9 Chemical Reactions 9.1 Reactions and Equations The process by which atoms of one or more substances are rearranged to form different substances is called a chemical reaction. There are a number

More information

Balancing Equations Notes

Balancing Equations Notes . Unit 9 Chemical Equations and Reactions What is a Chemical Equation? A is a written representation of the process that occurs in a chemical reaction. A chemical equation is written with the (starting

More information

The Mole. Relative Atomic Mass Ar

The Mole. Relative Atomic Mass Ar STOICHIOMETRY The Mole Relative Atomic Mass Ar Relative Molecular Mass Mr Defined as mass of one atom of the element when compared with 1/12 of an atom of carbon-12 Some Ar values are not whole numbers

More information

TOPIC 4: THE MOLE CONCEPTS

TOPIC 4: THE MOLE CONCEPTS TOPIC 4: THE MOLE CONCEPTS INTRODUCTION The mass is gram (g) of 1 mole of substances is called its.. 1 mole of substances has.. particles of a substances The mass of 1 mole of substances is always equal

More information

Balancing Equations Notes

Balancing Equations Notes . Unit 9 Chemical Equations and Reactions What is a Chemical Equation? A Chemical Equation is a written representation of the process that occurs in a chemical reaction. A chemical equation is written

More information

1.21. Formulae, equations and amounts of substance

1.21. Formulae, equations and amounts of substance 1.21. Formulae, equations and amounts of substance The mole is the key concept for chemical calculations DEFINITION: The mole is the amount of substance in grams that has the same number of particles as

More information

Regents Chemistry Unit 3- Bonding, Moles & Stoichiometry Study Guide & Pre-Test KEY

Regents Chemistry Unit 3- Bonding, Moles & Stoichiometry Study Guide & Pre-Test KEY Name: Regents Chemistry Unit 3- Bonding, Moles & Stoichiometry Study Guide & Pre-Test KEY Focus Questions for the Unit: How are compounds different... from elements?... from mixtures? What role do valence

More information

Unit 6: Stoichiometry. How do manufacturers know how to make enough of their desired product?

Unit 6: Stoichiometry. How do manufacturers know how to make enough of their desired product? Unit 6: Stoichiometry How do manufacturers know how to make enough of their desired product? Chocolate Chip Cookies Using the following recipe, complete the questions. Cookie Recipe 1.5 c sugar 1 c. butter

More information

Introduction to Chemical Reactions. Making new substances

Introduction to Chemical Reactions. Making new substances Introduction to Chemical Reactions Making new substances Main Ideas Chemical Reactions are represented by Chemical Equations. Chemical Equations are balanced to show the same number of atoms of each element

More information

Unit 4. Multiple Choice Identify the choice that best completes the statement or answers the question.

Unit 4. Multiple Choice Identify the choice that best completes the statement or answers the question. Unit 4 Multiple Choice Identify the choice that best completes the statement or answers the question. 39. Changing a subscript in a correctly written chemical formula a. changes the number of moles represented

More information

Intro to Reactions/ Balancing Equations

Intro to Reactions/ Balancing Equations Intro to Reactions/ Balancing Equations Chemical Reactions Chemical reactions involve change. Evidence of a chemical reaction could include the following Evolution of heat, light, and/or sound Production

More information

Stoichiometry CHAPTER 12

Stoichiometry CHAPTER 12 CHAPTER 12 Stoichiometry 12.1 Using Everyday Equations Stoichiometry is the calculation of quantities in chemical equations. * The balanced equation gives the ratios for the reactants and products. 3 eggs

More information

Quantitative Chemistry

Quantitative Chemistry Quantitative Chemistry When we do experiments to measure something in Chemistry, we: Repeat experiments (usually 3 times) to improve the reliability of the results, by calculating an average of our results.

More information

2. In which of these compounds are there twice as many oxygen atoms as hydrogen atoms? a. H 3 PO 4 c. HClO 3 b. H 2 SO 4 d. H 2 O

2. In which of these compounds are there twice as many oxygen atoms as hydrogen atoms? a. H 3 PO 4 c. HClO 3 b. H 2 SO 4 d. H 2 O Test Review Unit 3_3: Law of conservation of mass Identify the letter of the choice that best completes the statement or answers the question. At the end of the file you can find chemical equations to

More information

Representing Chemical Change

Representing Chemical Change Representing Chemical Change As we have already mentioned, a number of changes can occur when elements react with one another. These changes may either be physical or chemical. One way of representing

More information

Danyal Education (Contact: ) A commitment to teach and nurture

Danyal Education (Contact: ) A commitment to teach and nurture Chemistry of Reactions: Redox (#) Candidates should be able to: a) define oxidation and reduction (redox) in terms of oxygen/hydrogen gain/loss b) define redox in terms of electron transfer and changes

More information

CHEMICAL REACTIONS. Types of Reactions. Steps to Writing Reactions

CHEMICAL REACTIONS. Types of Reactions. Steps to Writing Reactions Types of Reactions CHEMICAL REACTIONS There are five types of chemical reactions we will talk about: 1. Synthesis reactions 2. reactions 3. Single displacement reactions 4. reactions 5. Combustion reactions

More information

Stoichiometry. Homework EC. cincochem.pbworks.com. Academic Chemistry DATE ASSIGNMENT

Stoichiometry. Homework EC. cincochem.pbworks.com. Academic Chemistry DATE ASSIGNMENT Unit 10 Resournces Name Academic Chemistry Stoichiometry Homework On-Time LATE DATE ASSIGNMENT 100 70 10.1 10.2 10.3 10.4 10.5 10.6 EC 16 cincochem.pbworks.com Stoichiometry Live in the now. Garth Algar

More information

IGCSE Double Award Extended Coordinated Science

IGCSE Double Award Extended Coordinated Science IGCSE Double Award Extended Coordinated Science Chemistry 4.0 - Chemical Formulae and Equations - the chemical symbols for the first 20 elements - And the charges of the ions they form - And use them to

More information

Unit Two Worksheet WS DC U2

Unit Two Worksheet WS DC U2 Unit Two Worksheet WS DC U2 Name Period Short Answer [Writing]. Write skeleton equations representing the following reactions and then balance them. Then identify the reaction type. Include all needed

More information

1. How many significant digits are there in each of the following measurements? (½ mark each) a) ha b) s. c) d) 0.

1. How many significant digits are there in each of the following measurements? (½ mark each) a) ha b) s. c) d) 0. SCH 4U_07-08 SCH3U: REVIEW NAME: (TOTAL SCORE = 80) 1. How many significant digits are there in each of the following measurements? (½ mark each) a) 204.45 ha b) 18.23 s c) 380 000 d) 0.00560 g 2. Name

More information

Unit 8 Chemical Reactions- Funsheets

Unit 8 Chemical Reactions- Funsheets Part A- Balancing Equations and Types of Reactions Balance AND identify the following reactions: Unit 8 Chemical Reactions- Funsheets 1) Mg + Zn(NO 3) 2 Zn Mg(NO 3) 2 2) Ba + AgNO 3 Ag + Ba(NO 3) 2 3)

More information

Science. Question. Percentage composition. Quantitative chemistry. Example

Science. Question. Percentage composition. Quantitative chemistry. Example Science Quantitative chemistry You should be able to calculate the masses of reactants and products from balanced equations, and the percentage composition by mass of an element in a compound. Higher tier

More information

1 Chemical Reactions and Equations

1 Chemical Reactions and Equations 1 Intext Questions On Page 6 Question 1. Why should a magnesium ribbon be cleaned before burning in air? Magnesium ribbon reacts with CO present in air to form a protective and inert layer of magnesium

More information

Ch 3.3 Counting (p78) One dozen = 12 things We use a dozen to make it easier to count the amount of substances.

Ch 3.3 Counting (p78) One dozen = 12 things We use a dozen to make it easier to count the amount of substances. Ch 3.3 Counting (p78) One dozen = 12 things We use a dozen to make it easier to count the amount of substances. Moles the SI base unit that describes the amount of particles in a substance. Mole is abbreviated

More information

UNIT 3 IB MATERIAL BONDING, MOLES & STOICHIOMETRY

UNIT 3 IB MATERIAL BONDING, MOLES & STOICHIOMETRY UNIT 3 IB MATERIAL Name: BONDING, MOLES & STOICHIOMETRY ESSENTIALS: Know, Understand, and Be Able To Apply the mole concept to substances. Determine the number of particles and the amount of substance

More information

LLT Education Services

LLT Education Services Rahul Arora 18. What chemical reaction is involved in the corrosion of iron? 19. Aluminum metal when burnt in air forms aluminium oxide. Write the balanced chemical equation for the reaction. 20. Is the

More information

CHEMICAL REACTIONS. The process by which one or more substances are changed into one or more different substances

CHEMICAL REACTIONS. The process by which one or more substances are changed into one or more different substances CHEMICAL REACTIONS The process by which one or more substances are changed into one or more different substances Equations Reactions are represented by a chemical equation Reactants Products Must have

More information

4-3 Quantitative chemistry Chemistry

4-3 Quantitative chemistry Chemistry 4-3 Quantitative chemistry Chemistry.0 This question is about carbonates.. Sodium carbonate, Na 2CO 3, is used as a water softener. Give the number of atoms of each type in sodium carbonate. [3 marks]

More information

Chapter 9: Stoichiometry The Arithmetic ti Of Equations

Chapter 9: Stoichiometry The Arithmetic ti Of Equations Chapter 9: Stoichiometry The Arithmetic of Equations Chemical Calculations Limiting Reagent and Percent Yield The Arithmetic ti Of Equations -- The Arithmetic of Equations -- Using Everyday Equations Stoichiometry

More information

Chapter 1 Chemical Reactions & Equations

Chapter 1 Chemical Reactions & Equations CBSE Class 10th NCERT Science Chapter 1 Chemical Reactions & Equations Intext Questions On Page 6 Question 1: Why should a magnesium ribbon be cleaned before burning in air? Magnesium is an extremely reactive

More information

CHEMICAL REACTIONS. Discuss breaking/forming bonds 10/29/2012. Products Reactants

CHEMICAL REACTIONS. Discuss breaking/forming bonds 10/29/2012. Products Reactants CHEMICAL REACTIONS - Page 321 Products Reactants Reactants: Zn + I 2 Product: Zn I 2 Discuss breaking/forming bonds Chemical Reaction or Change process in which one or more substances are converted into

More information

Slide 1 / 90. Stoichiometry HW. Grade:«grade» Subject: Date:«date»

Slide 1 / 90. Stoichiometry HW. Grade:«grade» Subject: Date:«date» Slide 1 / 90 Stoichiometry HW Grade:«grade» Subject: Date:«date» Slide 2 / 90 1 The calculation of quantities in chemical equations is called. A B C D E accuracy and precision dimensional analysis percent

More information

Please hand your completed booklet to your Chemistry tutor when you begin A Level Chemistry in September

Please hand your completed booklet to your Chemistry tutor when you begin A Level Chemistry in September #THIS I S TH E P L AC E A-LEVEL CHEMSITRY NAME: You should complete this work ready for starting Year 1 A Level Chemistry. If there are any questions that you cannot do, even after using your GCSE notes

More information

Questions Booklet. UNIT 1: Principles & Applications of Science I CHEMISTRY SECTION. Level 3 Applied Science. Name:.. Teacher:..

Questions Booklet. UNIT 1: Principles & Applications of Science I CHEMISTRY SECTION. Level 3 Applied Science. Name:.. Teacher:.. Level 3 Applied Science UNIT 1: Principles & Applications of Science I CHEMISTRY SECTION Questions Booklet Name:.. Teacher:.. Level 3 Applied Science 2017-2018 Unit 1 (Chemistry) 1 1. State the relative

More information

Unit 4: Reactions and Stoichiometry

Unit 4: Reactions and Stoichiometry Unit 4: Reactions and Stoichiometry Reactions Chemical equation Expression representing a chemical reaction Formulas of reactants on the left side Formulas of products on the right side Arrow(s) connect(s)

More information

Indicators of chemical reactions

Indicators of chemical reactions Indicators of chemical reactions Emission of light or heat Formation of a gas Formation of a precipitate Color change Emission of odor All chemical reactions: have two parts Reactants - the substances

More information

5. [7 points] What is the mass of gallons (a fifth) of pure ethanol (density = g/cm 3 )? [1 gallon = Liters]

5. [7 points] What is the mass of gallons (a fifth) of pure ethanol (density = g/cm 3 )? [1 gallon = Liters] 1 of 6 10/20/2009 3:55 AM Avogadro s Number, N A = 6.022 10 23 1. [7 points] Given the following mathematical expression: (15.11115.0)/(2.154 10 3 ) How many significant figures should the answer contain?

More information

Reaction Writing Sheet #1 Key

Reaction Writing Sheet #1 Key Reaction Writing Sheet #1 Key Write and balance each of the following reactions and indicate the reaction type(s) present: 1. zinc + sulfur zinc sulfide 8 Zn (s) + S 8 (s) 8 ZnS (s) synthesis 2. potassium

More information

Unit 5. Chemical Composition

Unit 5. Chemical Composition Unit 5 Chemical Composition Counting by Mass Individually mass a few Calculate the average mass of one Can count large numbers of by mass Atomic Mass Unit (amu) 1 amu = 1.66 x 10-24 g Subatomic particles

More information

Stoichiometry Part 1

Stoichiometry Part 1 Stoichiometry Part 1 Formulae of simple compounds Formulae of simple compounds can be deduced from their ions/valencies but there are some that you should know off by heart. You will learn these and more

More information

Chemical Reactions and Equations

Chemical Reactions and Equations Chemical Reactions and Equations 5-1 5.1 What is a Chemical Reaction? A chemical reaction is a chemical change. A chemical reaction occurs when one or more substances is converted into one or more new

More information

Types of Chemical Reactions

Types of Chemical Reactions Types of Chemical Reactions There are five types of chemical reactions: 1. Formation (combination) 2. Decomposition 3. Single Displacement 4. Double Displacement 5. Combustion 1 Formation (Combination)

More information

End of chapter exercises

End of chapter exercises End of chapter exercises Problem 1: Write only the word/term for each of the following descriptions: 1. the mass of one mole of a substance 2. the number of particles in one mole of a substance Answer

More information

TOPIC 9. CHEMICAL CALCULATIONS III - stoichiometry.

TOPIC 9. CHEMICAL CALCULATIONS III - stoichiometry. TOPIC 9. CHEMICAL CALCULATIONS III - stoichiometry. Stoichiometric calculations. By combining a knowledge of balancing equations with the concept of the mole, it is possible to easily calculate the masses

More information

Chapter 7. Chemical Reactions

Chapter 7. Chemical Reactions Chapter 7 Chemical Reactions 1 All chemical reactions have two parts Reactants - the substances you start with Products- the substances you end up with The reactants turn into the products. Reactants Products

More information

(i) Calculate the relative formula mass of carbon dioxide, CO 2.. (Relative atomic masses: C = 12, O = 16) (1) CaCO 3.

(i) Calculate the relative formula mass of carbon dioxide, CO 2.. (Relative atomic masses: C = 12, O = 16) (1) CaCO 3. 1 (a) Calcium oxide is manufactured by heating calcium carbonate. The waste product of this process is carbon dioxide. (i) Calculate the relative formula mass of carbon dioxide, CO 2. (Relative atomic

More information

TYPES OF CHEMICAL REACTIONS

TYPES OF CHEMICAL REACTIONS TYPES OF CHEMICAL REACTIONS Precipitation Reactions Compounds Soluble Ionic Compounds 1. Group 1A cations and NH 4 + 2. Nitrates (NO 3 ) Acetates (CH 3 COO ) Chlorates (ClO 3 ) Perchlorates (ClO 4 ) Solubility

More information

Describing Chemical Reactions

Describing Chemical Reactions Describing Chemical Reactions This section explains how to show chemical reactions with symbols. It also states the principle of conservation of mass, and identifies three categories of chemical reactions.

More information

SCH4U Chemistry Review: Fundamentals

SCH4U Chemistry Review: Fundamentals SCH4U Chemistry Review: Fundamentals Particle Theory of Matter Matter is anything that has mass and takes up space. Anything around us and in the entire universe can be classified as either matter or energy.

More information

5. The mass of oxygen required to completely convert 4.0 grams of hydrogen to water is 1) 8.0 grams; 2) 2.0 grams; 3) 32 grams; 4) 16 grams.

5. The mass of oxygen required to completely convert 4.0 grams of hydrogen to water is 1) 8.0 grams; 2) 2.0 grams; 3) 32 grams; 4) 16 grams. CHEMISTRY TEST NAME: MASS AND VOLUME DATE: EQUATION RELATIONSHIPS Directions: For each of the following questions, choose the number that best answers the question and place it on your answer sheet. Directions:

More information

Chemical Equations and Chemical Reactions

Chemical Equations and Chemical Reactions Chemical Equations Chemical Equations and Chemical Reactions Chemical equations are concise representations of chemical reactions. Chemical Equations Symbols Used in Chemical Equations The formulas of

More information