Study Guide For Chapter 7
|
|
- Esmond Martin Kelley
- 8 years ago
- Views:
Transcription
1 Name: Class: Date: ID: A Study Guide For Chapter 7 Multiple Choice Identify the choice that best completes the statement or answers the question. 1. The number of atoms in a mole of any pure substance is called a. its atomic number. c. its mass number. b. Avogadro s number. d. its gram-atomic number. 2. What can be said about 1 mol Ag and 1 mol Au? a. They are equal in mass. b. They contain the same number of atoms. c. Their molar masses are equal. d. They have the same atomic mass. 3. An Avogadro s number of any element is equivalent to a. the atomic number of that element. c particles. b. the mass number of that element. d. 12 g of that element. 4. If mol of Na + combines with mol of Cl to form NaCl, how many formula units of NaCl are present? a c b d Using a periodic table, what is the average atomic mass of zinc? a amu c amu b amu d amu 6. The atomic mass of hydrogen is amu. The reason that this value is not a whole number is that a. hydrogen only exists as a diatomic molecule. b. the mass of hydrogen is the sum of the masses of the protons and electrons in the atom. c. the mass of a proton is not exactly equal to 1 amu. d. hydrogen has more than one isotope. 7. A chemical formula includes the symbols of the elements in the compound and subscripts that indicate a. the number of formula units present. b. the number of atoms or ions of each type. c. the formula mass. d. the charges on the elements or ions. 8. How many atoms of fluorine are in a molecule of carbon tetrafluoride, CF 4? a. 1 c. 4 b. 2 d Changing a subscript in a correctly written chemical formula a. changes the number of moles represented by the formula. b. changes the charges on the other ions in the compound. c. changes the formula so that it no longer represents that compound. d. has no effect on the formula. 10. A formula that shows the simplest whole-number ratio of the atoms in a compound is the a. molecular formula. c. structural formula. b. ideal formula. d. empirical formula. 11. The molar mass of an element is the mass of one a. atom of the element. c. gram of the element. b. liter of the element. d. mole of the element. 1
2 Name: ID: A 12. To determine the molar mass of an element, one must know the element s a. Avogadro number. c. number of isotopes. b. atomic number. d. average atomic mass. 13. What is the molar mass of magnesium? a g c g b g d g 14. What is the empirical formula for a compound that is 31.9% potassium, 28.9% chlorine, and 39.2% oxygen? a. KClO 2 c. K 2 Cl 2 O 3 b. KClO 3 d. K 2 Cl 2 O What is the empirical formula for a compound that is 43.6% phosphorus and 56.4% oxygen? a. P 3 O 7 c. P 2 O 3 b. PO 3 d. P 2 O What is the empirical formula for a compound that is 53.3% O and 46.7% Si? a. SiO c. Si 2 O b. SiO 2 d. Si 2 O A compound contains g of F and 40.8 g of C. What is the empirical formula for this compound? a. CF 4 c. CF b. C 4 F d. CF A compound contains 64 g of O and 4 g of H. What is the empirical formula for this compound? a. H 2 O c. H 4 O 4 b. H 2 O 2 d. HO 19. What is the empirical formula for a compound that is 36.1% Ca and 63.9% Cl? a. CaCl c. CaCl 2 b. Ca 2 Cl d. Ca 2 Cl A compound contains 27.3 g of C and 72.7 g of O. What is the empirical formula for this compound? a. CO c. C 2 O b. CO 2 d. C 2 O To find the molecular formula from the empirical formula, one must determine the compound s a. density. c. structural formula. b. formula mass. d. crystal lattice. 22. A molecular compound has the empirical formula XY 3. Which of the following is a possible molecular formula? a. X 2 Y 3 c. X 2 Y 5 b. XY 4 d. X 2 Y The molecular formula for vitamin C is C 6 H 8 O 6. What is the empirical formula? a. CHO c. C 3 H 4 O 3 b. CH 2 O d. C 2 H 4 O A compound s empirical formula is NO 2. If the formula mass is 92 amu, what is the molecular formula? a. NO c. NO 2 b. N 2 O 2 d. N 2 O What is the percentage composition of CF 4? a. 20% C, 80% F c. 16.8% C, 83.2% F b. 13.6% C, 86.4% F d. 81% C, 19% F 26. What is the percentage composition of CuCl 2? a. 33% Cu, 66% Cl c % Cu, 34.50% Cl b. 50% Cu, 50% Cl d % Cu, % Cl 2
3 Name: ID: A 27. The percentage of sulfur in SO 2 is about 50%. What is the percentage of oxygen in this compound? a. 25% c. 75% b. 50% d. 90% 28. What is the percentage of OH in Ca(OH) 2? a. 45.9% c. 75% b. 66.6% d. 90.1% Completion Complete each statement. 29. As the atomic masses of the elements in the periodic table decreases, the number of atoms in one mole of the element. 30. The unit used for counting numbers of atoms, ions, or molecules is the. 31. If you have atoms of nickel, you have as the amount of nickel. 32. The number of eggs is to the number of dozens as the number of particles is to the number of. 33. In one mole of carbon dioxide, CO 2, there are oxygen atoms. 34. For sodium, the conversion factor that is used to change mass to moles is. 35. For potassium, the conversion factor that is used to change moles to mass is. 36. The conversion factor used to change moles to number of particles is. 37. The element that has an atomic mass of amu is. 38. The average atomic mass of cobalt is. 39. Comparing the average atomic masses of copper and zinc, the average atomic mass of is larger. 40. The empirical formula is always the accepted formula for a(n). 41. The empirical formula for a compound shows the symbols of the elements with subscripts indicating the. 42. In one mole of acetic acid, CH 3 COOH, there are moles of hydrogen atoms. 43. Two moles of carbon atoms are present in of C 6 H The unit used for molar mass is. 45. The molar mass of gallium is. 46. The molar mass of magnesium oxide, MgO, is. 47. The molar mass of barium nitrate, Ba(NO 3 ) 2, is. 48. The first step in finding an empirical formula from percentage composition is to assume that you have grams of sample. 49. To find an empirical formula from percentage composition, you must divide the number of grams of each element by that element s. 3
4 Name: ID: A 50. If, in determining the empirical formula from percentage composition, your first subscripts show the formula to be Fe 1 O 1.3, you must to obtain the final subscripts. 51. The empirical formula and the formula mass of a compound are needed to determine the compound s. 52. A compound s empirical formula is N 2 O 5. If the formula mass is 108 amu, its molecular formula is. 53. A compound s empirical formula is CH 3. If the formula mass is 30 amu, its molecular formula is. 54. To calculate the percentage composition of NiCl 2, you need to know. 55. The percentage of oxygen in NaOH is. 56. The percentage of sulfur in ammonium sulfate, (NH 4 ) 2 SO 4, is. Short Answer 57. Explain the relationship among , one mole, and g of carbon. 58. Why will one mole of copper(ii) chloride give you more chloride ions than one mole of copper(i) chloride? 59. Explain how you would determine the number of moles of aluminum in 96.7 g of aluminum. 60. Explain how you would calculate the mass in grams of one sodium atom. 61. Describe atomic mass. 62. Describe the atomic mass unit. 63. How are the atomic mass unit and the atomic mass related? 64. Why is the formula for ammonium sulfate written as (NH 4 ) 2 SO 4 and not as N 2 H 8 SO 4? 65. A student was supposed to find the molar mass of calcium nitrate, Ca(NO 3 ) 2. She added the molar masses of calcium, nitrogen, and oxygen. Explain why she did not get the correct value for the molar mass of the compound. 66. Explain the term empirical formula. What is the empirical formula of strontium bromide, SrBr 2? 67. You have samples of two compounds. Both contain only iron and chlorine. Explain what you would need to know to determine whether the two samples are the same compound or not. 68. Describe the steps used when determining a molecular formula, given an empirical formula and the molecular mass. 69. Explain how to calculate the percentage of aluminum in AlF 3. What is the percentage of Al in AlF 3? Problem 70. The mass of 1 mol of gold atoms is g. Find the mass of 1 atom of gold. 71. You have molecules of oxygen gas, O 2. What is the mass of that number of molecules? 4
5 Name: ID: A 72. What is the mass of 2.5 moles of carbon? 73. How many moles of copper are present in g Cu? 74. How many moles of oxygen atoms are present in 2.0 grams of oxygen gas, O 2? 75. Argentite is a silver ore that contains 87% silver and 13% sulfur. What is the empirical formula for argentite? 76. Calculate the percentage of sulfur in CuSO Calculate the percentage of oxygen in Fe 2 SiO Calculate the percentage of aluminum in Al 2 O 3. Essay 79. How can you count the number of atoms in a sample of a compound by using a balance? 80. Explain how a chemical formula is related to the mole. 81. Explain how a molecular formula is related to an empirical formula. 5
6 ID: A Study Guide For Chapter 7 Answer Section MULTIPLE CHOICE 1. ANS: B 2. ANS: B 3. ANS: C 4. ANS: A 5. ANS: D 6. ANS: D 7. ANS: B 8. ANS: C 9. ANS: C 10. ANS: D 11. ANS: D 12. ANS: D 13. ANS: C 14. ANS: B 15. ANS: D 16. ANS: B 17. ANS: A 18. ANS: D 19. ANS: C 20. ANS: B 21. ANS: B 22. ANS: D 23. ANS: C 24. ANS: D 25. ANS: B 26. ANS: D 27. ANS: B 28. ANS: A COMPLETION 29. ANS: stays the same 30. ANS: mole 31. ANS: two moles 1
7 ID: A 32. ANS: moles 33. ANS: ANS: 1 mol/22.99 g 35. ANS: g/1 mol 36. ANS: particles/1 mol 37. ANS: Ca 38. ANS: amu 39. ANS: copper 40. ANS: ionic compound 41. ANS: smallest whole-number ratio of the atoms 42. ANS: four 43. ANS: 0.33 mol one-third mole 44. ANS: g/mol 45. ANS: g/mol 46. ANS: g/mol 2
8 ID: A 47. ANS: g/mol 48. ANS: ANS: molar mass 50. ANS: multiply the subscripts by ANS: molecular formula 52. ANS: N 2 O ANS: C 2 H ANS: the molar masses of Ni, Cl, and NiCl ANS: 40.00% 56. ANS: 24.26% SHORT ANSWER 57. ANS: One mole of something equal units of it. The number was defined as the number of carbon atoms in exactly g of carbon. 58. ANS: One mole of copper(ii) chloride, CuCl 2, provides two moles of Cl ion per mole of compound. Because copper(i) chloride, CuCl, contains only one mole of Cl ion per mole of compound, it produces fewer chloride ions. 3
9 ID: A 59. ANS: You would multiply 96.7 g Al by the mol by the conversion factor 1 mol Al/26.98 g Al. (You would divide 96.7 g Al by the molar mass of Al.) 60. ANS: You would multiply the molar mass of sodium, g/mol, by the conversion factor 1 mol/ atoms. 61. ANS: Atomic mass is the sum of the masses of the total number of protons and neutrons in the atom. 62. ANS: The atomic mass unit is the average of the mass of the protons and neutrons in the carbon-12 isotope. 63. ANS: The atomic mass is the atomic mass unit multiplied by the number of protons and neutrons in the atom. 64. ANS: NH 4 + is a polyatomic ion that remains a unit and must be treated as a unit in the formula. 65. ANS: One mole of the compound contains one mole of Ca, but it contains two moles of N and six moles of O. By adding the mass of one mole of each, the value did not include the mass of the other N and the other five O atoms. 66. ANS: The empirical formula shows the simplest whole-number ratio of the atoms that form a compound. The simplest ratio in which strontium and bromine combine is 1:2, so the empirical formula is SrBr ANS: You would need to know the percentage of iron and chlorine in both samples. If the percentage of iron and the percentage of chlorine are the same for both samples, the compounds are the same. 68. ANS: Find the mass of the empirical formula. Divide the molecular mass by the mass of the empirical formula. Multiply the subscripts in the empirical formula by this quotient. 4
10 ID: A 69. ANS: Divide the molar mass of Al, g/mol, by the molar mass of the compound, g/mol, then multiply the quotient by 100. The compound is % Al. PROBLEM 70. ANS: gAu 1molAu 1molAu atomsau = g/atomau 71. ANS: 1molO molecules molecules O gO 2 1molO2 = 0.085gO2 72. ANS: 2.5moles C 12.01gC 1molC = gc 73. ANS: 180.0gCu 1molCu = 63.55gCu 2.832molCu 74. ANS: 2.0gO 2 1molO gO 2 2molOatoms 1molO 2 =0.12mol O atoms 75. ANS: 87gAg 1molAg gAg =0.81molAg 13gS 1mol S 32.07gS =0.41mol S 2 mol Ag: 1 mol S; Ag 2 S 5
11 ID: A 76. ANS: 32.07g/mol 100=20.09% S g/mol 77. ANS: 64.00g/mol 100=31.40% O g/mol 78. ANS: %Al= 53.96g/mol 100=52.92% Al g/mol ESSAY 79. ANS: First, determine the molar mass of the compound. This mass is the amount of compound present in one mole and the amount of compound that contains formula units of the compound. Then, find the mass of the sample. Divide the sample mass by the molar mass to find out what fraction of a mole is present. Then multiply this number by to determine the number of formula units present. Multiply this result by the number of atoms present in one formula unit of the compound. 80. ANS: The chemical formula identifies the number of each type of element present in a compound. This number is identified as a subscript for values greater than 1, and represents the number of moles of that element present in one mole of the compound. 81. ANS: The empirical formula is the simplest ratio of the elements in a compound. The empirical formula is the one used for an ionic compound. The molecular compound shows the actual composition of a molecule and is a multiple of the empirical formula. The empirical and molecular formulas can be the same if the atoms in the molecule exist in the simplest ratio. 6
12 Study Guide For Chapter 7 [Answer Strip] ID: A D 12. B 27. C 13. A 28. B 1. B 14. B 2. D 15. C 3. A 4. B 16. A 17. D 18. D 5. D 6. C 19. B 20. B 7. B 21. D 22. C 8. C 9. C 23. D 24. D 10. B 25. D 11. D 26.
How much does a single atom weigh? Different elements weigh different amounts related to what makes them unique.
How much does a single atom weigh? Different elements weigh different amounts related to what makes them unique. What units do we use to define the weight of an atom? amu units of atomic weight. (atomic
More informationChemistry 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
More informationMoles, Molecules, and Grams Worksheet Answer Key
Moles, Molecules, and Grams Worksheet Answer Key 1) How many are there in 24 grams of FeF 3? 1.28 x 10 23 2) How many are there in 450 grams of Na 2 SO 4? 1.91 x 10 24 3) How many grams are there in 2.3
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 informationThe 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
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 informationChapter 4. Chemical Composition. Chapter 4 Topics H 2 S. 4.1 Mole Quantities. The Mole Scale. Molar Mass The Mass of 1 Mole
Chapter 4 Chemical Composition Chapter 4 Topics 1. Mole Quantities 2. Moles, Masses, and Particles 3. Determining Empirical Formulas 4. Chemical Composition of Solutions Copyright The McGraw-Hill Companies,
More informationCh. 10 The Mole I. Molar Conversions
Ch. 10 The Mole I. Molar Conversions I II III IV A. What is the Mole? A counting number (like a dozen) Avogadro s number (N A ) 1 mole = 6.022 10 23 representative particles B. Mole/Particle Conversions
More informationSCH 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
More informationChapter 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
More informationMolar Mass Worksheet Answer Key
Molar Mass Worksheet Answer Key Calculate the molar masses of the following chemicals: 1) Cl 2 71 g/mol 2) KOH 56.1 g/mol 3) BeCl 2 80 g/mol 4) FeCl 3 162.3 g/mol 5) BF 3 67.8 g/mol 6) CCl 2 F 2 121 g/mol
More informationMoles. 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)
More informationChemical Composition Review Mole Calculations Percent Composition. Copyright Cengage Learning. All rights reserved. 8 1
Chemical Composition Review Mole Calculations Percent Composition Copyright Cengage Learning. All rights reserved. 8 1 QUESTION Suppose you work in a hardware store and a customer wants to purchase 500
More informationCalculation of Molar Masses. Molar Mass. Solutions. Solutions
Molar Mass Molar mass = Mass in grams of one mole of any element, numerically equal to its atomic weight Molar mass of molecules can be determined from the chemical formula and molar masses of elements
More informationDescription of the Mole Concept:
Description of the Mole Concept: Suppose you were sent into the store to buy 36 eggs. When you picked them up you would get 3 boxes, each containing 12 eggs. You just used a mathematical device, called
More informationChapter 1: Moles and equations. Learning outcomes. you should be able to:
Chapter 1: Moles and equations 1 Learning outcomes you should be able to: define and use the terms: relative atomic mass, isotopic mass and formula mass based on the 12 C scale perform calculations, including
More information602X10 21 602,000,000,000, 000,000,000,000 6.02X10 23. Pre- AP Chemistry Chemical Quan44es: The Mole. Diatomic Elements
Pre- AP Chemistry Chemical Quan44es: The Mole Mole SI unit of measurement that measures the amount of substance. A substance exists as representa9ve par9cles. Representa9ve par9cles can be atoms, molecules,
More informationPart One: Mass and Moles of Substance. Molecular Mass = sum of the Atomic Masses in a molecule
CHAPTER THREE: CALCULATIONS WITH CHEMICAL FORMULAS AND EQUATIONS Part One: Mass and Moles of Substance A. Molecular Mass and Formula Mass. (Section 3.1) 1. Just as we can talk about mass of one atom of
More informationU3-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
More informationCHEMICAL FORMULAS AND FORMULA WEIGHT CALCULATIONS
CHEMICAL FORMULAS AND FORMULA WEIGHT CALCULATIONS 1. THE MEANING OF A CHEMICAL FORMULA A chemical formula is a shorthand method of representing the elements in a compound. The formula shows the formulas
More informationW1 WORKSHOP ON STOICHIOMETRY
INTRODUCTION W1 WORKSHOP ON STOICHIOMETRY These notes and exercises are designed to introduce you to the basic concepts required to understand a chemical formula or equation. Relative atomic masses of
More informationMOLECULAR MASS AND FORMULA MASS
1 MOLECULAR MASS AND FORMULA MASS Molecular mass = sum of the atomic weights of all atoms in the molecule. Formula mass = sum of the atomic weights of all atoms in the formula unit. 2 MOLECULAR MASS AND
More informationThe Mole. 6.022 x 10 23
The Mole 6.022 x 10 23 Background: atomic masses Look at the atomic masses on the periodic table. What do these represent? E.g. the atomic mass of Carbon is 12.01 (atomic # is 6) We know there are 6 protons
More informationThe Mole. Chapter 2. Solutions for Practice Problems
Chapter 2 The Mole Note to teacher: You will notice that there are two different formats for the Sample Problems in the student textbook. Where appropriate, the Sample Problem contains the full set of
More informationThe Mole. Chapter 10. Dimensional Analysis. The Mole. How much mass is in one atom of carbon-12? Molar Mass of Atoms 3/1/2015
The Mole Chapter 10 1 Objectives Use the mole and molar mass to make conversions among moles, mass, and number of particles Determine the percent composition of the components of a compound Calculate empirical
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 information= 16.00 amu. = 39.10 amu
Using Chemical Formulas Objective 1: Calculate the formula mass or molar mass of any given compound. The Formula Mass of any molecule, formula unit, or ion is the sum of the average atomic masses of all
More informationCHAPTER 3 Calculations with Chemical Formulas and Equations. atoms in a FORMULA UNIT
CHAPTER 3 Calculations with Chemical Formulas and Equations MOLECULAR WEIGHT (M. W.) Sum of the Atomic Weights of all atoms in a MOLECULE of a substance. FORMULA WEIGHT (F. W.) Sum of the atomic Weights
More informationElement of same atomic number, but different atomic mass o Example: Hydrogen
Atomic mass: p + = protons; e - = electrons; n 0 = neutrons p + + n 0 = atomic mass o For carbon-12, 6p + + 6n 0 = atomic mass of 12.0 o For chlorine-35, 17p + + 18n 0 = atomic mass of 35.0 atomic mass
More informationMultiple Choice Identify the letter of the choice that best completes the statement or answers the question.
Introduction to Chemistry Exam 2 Practice Problems 1 Multiple Choice Identify the letter of the choice that best completes the statement or answers the question. 1.Atoms consist principally of what three
More informationCalculating Atoms, Ions, or Molecules Using Moles
TEKS REVIEW 8B Calculating Atoms, Ions, or Molecules Using Moles TEKS 8B READINESS Use the mole concept to calculate the number of atoms, ions, or molecules in a sample TEKS_TXT of material. Vocabulary
More information1. 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?
More informationSolution. Practice Exercise. Concept Exercise
Example Exercise 9.1 Atomic Mass and Avogadro s Number Refer to the atomic masses in the periodic table inside the front cover of this textbook. State the mass of Avogadro s number of atoms for each of
More informationChapter 1 The Atomic Nature of Matter
Chapter 1 The Atomic Nature of Matter 6. Substances that cannot be decomposed into two or more simpler substances by chemical means are called a. pure substances. b. compounds. c. molecules. d. elements.
More informationConcept 1. The meaning and usefulness of the mole. The mole (or mol) represents a certain number of objects.
Chapter 3. Stoichiometry: Mole-Mass Relationships in Chemical Reactions Concept 1. The meaning and usefulness of the mole The mole (or mol) represents a certain number of objects. SI def.: the amount of
More informationMatter. Atomic weight, Molecular weight and Mole
Matter Atomic weight, Molecular weight and Mole Atomic Mass Unit Chemists of the nineteenth century realized that, in order to measure the mass of an atomic particle, it was useless to use the standard
More informationCHAPTER 8: CHEMICAL COMPOSITION
CHAPTER 8: CHEMICAL COMPOSITION Active Learning: 1-4, 6-8, 12, 18-25; End-of-Chapter Problems: 3-4, 9-82, 84-85, 87-92, 94-104, 107-109, 111, 113, 119, 125-126 8.2 ATOMIC MASSES: COUNTING ATOMS BY WEIGHING
More informationChemistry 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
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 informationName Date Class CHEMICAL QUANTITIES. SECTION 10.1 THE MOLE: A MEASUREMENT OF MATTER (pages 287 296)
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 you how to calculate
More informationPeriodic Table, Valency and Formula
Periodic Table, Valency and Formula Origins of the Periodic Table Mendelѐѐv in 1869 proposed that a relationship existed between the chemical properties of elements and their atomic masses. He noticed
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 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 informationChapter 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
More informationPART 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
More informationLecture 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?
More informationSample Exercise 2.1 Illustrating the Size of an Atom
Sample Exercise 2.1 Illustrating the Size of an Atom The diameter of a US penny is 19 mm. The diameter of a silver atom, by comparison, is only 2.88 Å. How many silver atoms could be arranged side by side
More informationProblem Solving. Empirical Formulas
Skills Worksheet Problem Solving Empirical Formulas Suppose you analyze an unknown compound that is a white powder and find that it is composed of 36.5% sodium, 38.1% oxygen, and 25.4% sulfur. You can
More information10 The Mole. Section 10.1 Measuring Matter
Name Date Class The Mole Section.1 Measuring Matter In your textbook, read about counting particles. In Column B, rank the quantities from Column A from smallest to largest. Column A Column B 0.5 mol 1.
More informationThe Mole Concept. The Mole. Masses of molecules
The Mole Concept Ron Robertson r2 c:\files\courses\1110-20\2010 final slides for web\mole concept.docx The Mole The mole is a unit of measurement equal to 6.022 x 10 23 things (to 4 sf) just like there
More informationChemistry 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
More informationAmount of Substance. http://www.avogadro.co.uk/definitions/elemcompmix.htm
Page 1 of 14 Amount of Substance Key terms in this chapter are: Element Compound Mixture Atom Molecule Ion Relative Atomic Mass Avogadro constant Mole Isotope Relative Isotopic Mass Relative Molecular
More informationCh. 6 Chemical Composition and Stoichiometry
Ch. 6 Chemical Composition and Stoichiometry The Mole Concept [6.2, 6.3] Conversions between g mol atoms [6.3, 6.4, 6.5] Mass Percent [6.6, 6.7] Empirical and Molecular Formula [6.8, 6.9] Bring your calculators!
More informationA dozen. Molar Mass. Mass of atoms
A dozen Molar Mass Science 10 is a number of objects. A dozen eggs, a dozen cars, and a dozen people are all 12 objects. But a dozen cars has a much greater mass than a dozen eggs because the mass of each
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 informationUnit 9 Compounds Molecules
Unit 9 Compounds Molecules INTRODUCTION Compounds are the results of combinations of elements. These new substances have unique properties compared to the elements that make them up. Compounds are by far
More informationWoods Chem-1 Lec-02 10-1 Atoms, Ions, Mole (std) Page 1 ATOMIC THEORY, MOLECULES, & IONS
Woods Chem-1 Lec-02 10-1 Atoms, Ions, Mole (std) Page 1 ATOMIC THEORY, MOLECULES, & IONS Proton: A positively charged particle in the nucleus Atomic Number: We differentiate all elements by their number
More information2 The Structure of Atoms
CHAPTER 4 2 The Structure of Atoms SECTION Atoms KEY IDEAS As you read this section, keep these questions in mind: What do atoms of the same element have in common? What are isotopes? How is an element
More informationMoles. 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
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 informationTOPIC 7. CHEMICAL CALCULATIONS I - atomic and formula weights.
TOPIC 7. CHEMICAL CALCULATIONS I - atomic and formula weights. Atomic structure revisited. In Topic 2, atoms were described as ranging from the simplest atom, H, containing a single proton and usually
More informationChemical Composition. Introductory Chemistry: A Foundation FOURTH EDITION. Atomic Masses. Atomic Masses. Atomic Masses. Chapter 8
Introductory Chemistry: A Foundation FOURTH EDITION by Steven S. Zumdahl University of Illinois Chemical Composition Chapter 8 1 2 Atomic Masses Balanced equation tells us the relative numbers of molecules
More informationWRITING CHEMICAL FORMULA
WRITING CHEMICAL FORMULA For ionic compounds, the chemical formula must be worked out. You will no longer have the list of ions in the exam (like at GCSE). Instead you must learn some and work out others.
More informationOther 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
More informationneutrons 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
More informationStoichiometry. 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
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 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 informationMole Calculations Multiple Choice Review PSI Chemistry
Mole Calculations Multiple Choice Review PSI Chemistry Name The Mole and Avogadro's Number 1)What is the SI unit for measurement of number of particles in a substance? A) kilogram B) ampere C) candela
More informationName: Class: Date: 2 4 (aq)
Name: Class: Date: Unit 4 Practice Test Multiple Choice Identify the choice that best completes the statement or answers the question. 1) The balanced molecular equation for complete neutralization of
More informationb. N 2 H 4 c. aluminum oxalate d. acetic acid e. arsenic PART 2: MOLAR MASS 2. Determine the molar mass for each of the following. a. ZnI 2 b.
CHEMISTRY DISCOVER UNIT 5 LOTS OF PRACTICE ON USING THE MOLE!!! PART 1: ATOMIC MASS, FORMULA MASS, OR MOLECULAR MASS 1. Determine the atomic mass, formula mass, or molecular mass for each of the following
More informationStoichiometry 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
More informationSample Exercise 3.1 Interpreting and Balancing Chemical Equations
Sample Exercise 3.1 Interpreting and Balancing Chemical Equations The following diagram represents a chemical reaction in which the red spheres are oxygen atoms and the blue spheres are nitrogen atoms.
More informationBalance 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
More informationChapter 5. Chapter 5. Naming Ionic Compounds. Objectives. Chapter 5. Chapter 5
Objectives Name cations, anions, and ionic compounds. Write chemical formulas for ionic compounds such that an overall neutral charge is maintained. Explain how polyatomic ions and their salts are named
More informationProblem Solving. Percentage Composition
Skills Worksheet Problem Solving Percentage Composition Suppose you are working in an industrial laboratory. Your supervisor gives you a bottle containing a white crystalline compound and asks you to determine
More informationStoichiometry. 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
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 informationFormulae, 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
More information19.2 Chemical Formulas
In the previous section, you learned how and why atoms form chemical bonds with one another. You also know that atoms combine in certain ratios with other atoms. These ratios determine the chemical formula
More informationCHEMICAL FORMULAS AND FORMULA WEIGHT CALCULATIONS
CHEMICAL FORMULAS AND FORMULA WEIGHT CALCULATIONS 1. THE MEANING OF A CHEMICAL FORMULA A chemical formula is a shorthand method of representing the elements in a compound. The formula shows the formulas
More information1. 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)
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 informationCONSERVATION 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)
More informationProblem Solving. Mole Concept
Skills Worksheet Problem Solving Mole Concept Suppose you want to carry out a reaction that requires combining one atom of iron with one atom of sulfur. How much iron should you use? How much sulfur? When
More informationBalancing 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
More informationName 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
More informationBalancing 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.
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 informationA 1.008 g sample of H contains 6.0221415 x 10 23 H atoms.
7 Chemical Composition 7. Avogadro s umber n 8, the talian scientist, Amadeo Avogadro proposed that: Equal volumes of gas at equal temperatures and pressures have the same number of particles. This law,
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 information= 11.0 g (assuming 100 washers is exact).
CHAPTER 8 1. 100 washers 0.110 g 1 washer 100. g 1 washer 0.110 g = 11.0 g (assuming 100 washers is exact). = 909 washers 2. The empirical formula is CFH from the structure given. The empirical formula
More informationTHE MOLE / COUNTING IN CHEMISTRY
1 THE MOLE / COUNTING IN CHEMISTRY ***A mole is 6.0 x 10 items.*** 1 mole = 6.0 x 10 items 1 mole = 60, 00, 000, 000, 000, 000, 000, 000 items Analogy #1 1 dozen = 1 items 18 eggs = 1.5 dz. - to convert
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 informationChapter 8 How to Do Chemical Calculations
Chapter 8 How to Do Chemical Calculations Chemistry is both a qualitative and a quantitative science. In the laboratory, it is important to be able to measure quantities of chemical substances and, as
More informationSTOICHIOMETRY UNIT 1 LEARNING OUTCOMES. At the end of this unit students will be expected to:
STOICHIOMETRY LEARNING OUTCOMES At the end of this unit students will be expected to: UNIT 1 THE MOLE AND MOLAR MASS define molar mass and perform mole-mass inter-conversions for pure substances explain
More informationFormulas, 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
More informationWe know from the information given that we have an equal mass of each compound, but no real numbers to plug in and find moles. So what can we do?
How do we figure this out? We know that: 1) the number of oxygen atoms can be found by using Avogadro s number, if we know the moles of oxygen atoms; 2) the number of moles of oxygen atoms can be found
More informationChemical Proportions in Compounds
Chapter 6 Chemical Proportions in Compounds Solutions for Practice Problems Student Textbook page 201 1. Problem A sample of a compound is analyzed and found to contain 0.90 g of calcium and 1.60 g of
More information3.3 Moles, 3.4 Molar Mass, and 3.5 Percent Composition
3.3 Moles, 3.4 Molar Mass, and 3.5 Percent Composition 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 Copyright
More information