Temperature. Number of moles. Constant Terms. Pressure. Answers Additional Questions 12.1

Size: px
Start display at page:

Download "Temperature. Number of moles. Constant Terms. Pressure. Answers Additional Questions 12.1"

Transcription

1 Answers Additional Questions A gas collected over water has a total pressure equal to the pressure of the dry gas plus the pressure of the water vapor. If the partial pressure of water at 25.0 degrees Celsius is 3.2 KPa and the total pressure is KPa, what fraction of the total pressure is the water vapor? Pressure H 2 O = Molecules H 2 O = Volume H 2 O Total Pressure Total Molecules Total Volume 3.2 KPa = 3.2% water vapor KPA 2. Divers under great pressure breath a mixture of 79% helium and 21% oxygen by volume to prevent nitrogen from being forced into the bloodstream. If the tank's total pressure is 9120 mm Hg what is the partial pressure of oxygen? Pressure O 2 = 21% 0.21 * 9120 mmhg = 1900 mmhg O 2 Total Pressure 3. What conditions are held constant in Charles' Law? # moles and pressure are constant Volume P V = N R T Constant Temperature Pressure Number of moles Volume = Number Moles * Constant Temperature Pressure Constant Terms Volume 1 = Volume 2 Temperature must be in Kelvin Temperature 1 Temperature 2 Volume is directly proportional to Temperature Why does a gas expand when heated? Think of a balloon as having constant pressure due to the flexibility of the covering. As the temperature increases the kinetic energy of the gas increases, causing the molecules to move faster, striking the covering more often and with greater force. The covering expands under the increased force making the volume larger.

2 4. A balloon with a volume of 1.35 liters at 27.0 degrees Celsius is brought outside to a temperature of 12.0 degrees Celsius. What will the new volume of the balloon be? V1 = 1.35 liters V2 =? T1 = 27 Celsius T2 = 12 Celsius Kelvin = Celsius Kelvin 285 Kelvin P1 = P2 Volume 1 = Volume L = V2 V2 = 1.28 L Temperature 1 Temperature K 285 K 5. What conditions are held constant in Gay-Lussac's Law? # moles, volume constant Constant terms P = N * R P1 = P2 T V T1 T2 Pressure is directly proportional to temperature (Kelvin) Why does the pressure of a gas decrease when it's cooled? As temperature decreases the kinetic energy drops, decreasing the number of collisions and the force of collisions with the container walls. 6. A car tire with a constant volume is filled with 202 KPa pressure at 25.0 Degrees Celsius when a trip begins. What will the new tire pressure be if the temperature rises to 30.0 Degrees Celsius during the trip? P1 = 202 KPa P2 =? T1 = 25 Celsius T2= 30 Celsius 298 Kelvin 303 Kelvin V1 = V2 P1 = P2 202 KPa = P2 P2 = 205 KPa T1 T2 298 K 303 K 7. A diver needs to compress liters of air at 760 mm Hg pressure into a tank with a volume of 30.0 liters. If the temperature stays the same, what will the air pressure in the tank be? V1 = 400 L V2 = 30 L P1 = 760 mm Hg P2 =? T1 = T2 P * V = N * R * T Constant terms Pressure is inversely proportional to volume (Boyles Law) 400 L * 760 mmhg = P2 * 30 L P2 = mmhg P1 * V1 = P2 * V2

3 8. A weather balloon with 775 liters of gas is released at 102 KPa pressure and 25.0 Degrees Celsius. What will its volume be when it reaches maximum height with a pressure of 45 KPa and a temperature of 5.7 Degrees Celsius? V1 = 775 L V2 =? P1 = 102 KPa P2 = 45 KPa T1 = 25 Celsius T2 = 5.7 Celsius 298 Kelvin 279 Kelvin Constant Terms P * V = N * R P1 V1 = P2 V2 (Combined Gas law) T T1 T2 102 KPa 775 L = 45 KPa V2 V2 = 1640 L 298 Kelvin 279 Kelvin 9. Standard temperature is 0 degrees Celsius (273 Kelvin), standard pressure is 760 mm Hg (101.3 KPa). If 1.0 mole of a gas occupies 22.4 liters at standard temperature and pressure, calculate the ideal gas law constant R for volume in liters and pressure in mmhg. R = P * V = 760 mmhg 22.4 L = 62.4 mmhg L N * T 1.0 mole 273 Kelvin or KPa 22.4 L = 8.31 KPa L 1.0 mole 273 Kelvin 10. Use the ideal gas law to find the volume of 13.5 grams of nitrogen gas at 105 KPa and 29.0 degrees Celsius. Hint: Convert grams to moles g N 2 * 1 mole N 2 =.482 moles N g N 2 V = N * R * T = moles * 8.31 KPa L * 302 Kelvin = 11.5 L P mole Kevin 105 KPa 11. What mass will 5.75 liters of carbon dioxide gas have at 97.5 KPa and 17.0 degrees Celsius? Hint: Find moles and convert to grams. N = P * V = 97.5 KPa 5.75 L = moles R * T 8.31 KPa L 280 Kelvin moles CO 2 * 44.0 grams CO 2 = 10.3 g CO 2 1 mole CO 2

4 12. What is the density of water vapor at 25.0 Degrees Celsius and 755 mm Hg pressure? Hint: Find the mass and volume of 1.0 mole of water vapor. N = P = 755 mmhg = mole V R * T 62.4 mmhg L 298 Kelvin L mole H 2 O * 18.0 g H 2 O = g 1 mole H 2 O L 13. What volume of oxygen gas is produced when 37.5 grams of potassium chlorate decomposes at 45.0 degrees Celsius and 115 KPa pressure? Hint: Find the moles of oxygen gas produced and then calculate the volume. 2 KClO 3 -> 2 KCl + 3 O g KClO 3 * 1 mole KClO 3 * 3 moles O 2 = mole O grams KClO 3 2 moles KClO 3 V= N * R * T = moles * 8.31 KPa L 318 Kelvin = 10.5 L O KPa 14. Show that the volume of a gas is directly proportional to the number of moles of the gas if the pressure and temperature are held constant. (Think of blowing up a balloon) P * V = N * R * T P, V constant V = R * T V1 = V2 Volume is directly proportional N P N1 N2 to number of moles liters of nitrogen gas and 3.5 liters of hydrogen gas react at constant temperature and pressure to produce ammonia (NH 3 ). What volume of ammonia is produced? Hint: Use the proportion in question 17. N H 2 -> 2 NH 3 Since the temperature and pressure are constant the ratio of moles is also the ratio of gas volumes 1.5 L N 2 * 2 moles NH 3 = 3.0 L NH 3 1 mole N L H 2 * 2 moles NH 3 =2.3 L NH 3 3 moles H 2 Hydrogen gas limits the reaction because it produces a smaller amount of ammonia gas.

5 16. Air has an average mass of 29 amu. What is the ratio of velocities between air and gasoline vapor (C 8 H 18 ) if the temperature is the same? Graham's Law Velocity of gas 1 = Mass of gas 2 Velocity of gas 2 Mass of gas 1 At equal temperatures the heavier gases travel more slowly Velocity Air = Mass of Gasoline = 114 amu = 2.0 Velocity Gasoline Mass Air 29 amu The air travels at twice the speed of gasoline vapor 17. A chemist collects 1040 ml of gas over water at 25 Degrees Celsius and 122 KPa total pressure. The partial pressure of water at 25 degrees Celsius is 3.2 KPa. What is the volume of the dry gas at standard temperature and pressure? Percentage = Pressure = Total - Water vapor = 122 KPa KPa = 97% dry gas dry gas pressure pressure 122 KPa Total pressure Total pressure Percentage of = Percentage of = Percentage of Dry gas pressure Dry gas volume moles of Dry gas 0.97 % * 1040 ml = 1009 ml of Dry Gas

Gas Laws. The kinetic theory of matter states that particles which make up all types of matter are in constant motion.

Gas Laws. The kinetic theory of matter states that particles which make up all types of matter are in constant motion. Name Period Gas Laws Kinetic energy is the energy of motion of molecules. Gas state of matter made up of tiny particles (atoms or molecules). Each atom or molecule is very far from other atoms or molecules.

More information

The Gas Laws. Our Atmosphere. Pressure = Units of Pressure. Barometer. Chapter 10

The Gas Laws. Our Atmosphere. Pressure = Units of Pressure. Barometer. Chapter 10 Our Atmosphere The Gas Laws 99% N 2 and O 2 78% N 2 80 70 Nitrogen Chapter 10 21% O 2 1% CO 2 and the Noble Gases 60 50 40 Oxygen 30 20 10 0 Gas Carbon dioxide and Noble Gases Pressure Pressure = Force

More information

Kinetic Theory of Gases. 6.1 Properties of Gases 6.2 Gas Pressure. Properties That Describe a Gas. Gas Pressure. Learning Check.

Kinetic Theory of Gases. 6.1 Properties of Gases 6.2 Gas Pressure. Properties That Describe a Gas. Gas Pressure. Learning Check. Chapter 6 Gases Kinetic Theory of Gases 6.1 Properties of Gases 6.2 Gas Pressure A gas consists of small particles that move rapidly in straight lines. have essentially no attractive (or repulsive) forces.

More information

CHEMISTRY GAS LAW S WORKSHEET

CHEMISTRY GAS LAW S WORKSHEET Boyle s Law Charles Law Guy-Lassac's Law Combined Gas Law For a given mass of gas at constant temperature, the volume of a gas varies inversely with pressure PV = k The volume of a fixed mass of gas is

More information

7. 1.00 atm = 760 torr = 760 mm Hg = 101.325 kpa = 14.70 psi. = 0.446 atm. = 0.993 atm. = 107 kpa 760 torr 1 atm 760 mm Hg = 790.

7. 1.00 atm = 760 torr = 760 mm Hg = 101.325 kpa = 14.70 psi. = 0.446 atm. = 0.993 atm. = 107 kpa 760 torr 1 atm 760 mm Hg = 790. CHATER 3. The atmosphere is a homogeneous mixture (a solution) of gases.. Solids and liquids have essentially fixed volumes and are not able to be compressed easily. have volumes that depend on their conditions,

More information

CHAPTER 12. Gases and the Kinetic-Molecular Theory

CHAPTER 12. Gases and the Kinetic-Molecular Theory CHAPTER 12 Gases and the Kinetic-Molecular Theory 1 Gases vs. Liquids & Solids Gases Weak interactions between molecules Molecules move rapidly Fast diffusion rates Low densities Easy to compress Liquids

More information

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Chapter 10 MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) A gas at a pressure of 10.0 Pa exerts a force of N on an area of 5.5 m2. A) 1.8 B) 0.55

More information

= 1.038 atm. 760 mm Hg. = 0.989 atm. d. 767 torr = 767 mm Hg. = 1.01 atm

= 1.038 atm. 760 mm Hg. = 0.989 atm. d. 767 torr = 767 mm Hg. = 1.01 atm Chapter 13 Gases 1. Solids and liquids have essentially fixed volumes and are not able to be compressed easily. Gases have volumes that depend on their conditions, and can be compressed or expanded by

More information

Gas Laws. vacuum. 760 mm. air pressure. mercury

Gas Laws. vacuum. 760 mm. air pressure. mercury Gas Laws Some chemical reactions take place in the gas phase and others produce products that are gases. We need a way to measure the quantity of compounds in a given volume of gas and relate that to moles.

More information

CHEMISTRY. Matter and Change. Section 13.1 Section 13.2 Section 13.3. The Gas Laws The Ideal Gas Law Gas Stoichiometry

CHEMISTRY. Matter and Change. Section 13.1 Section 13.2 Section 13.3. The Gas Laws The Ideal Gas Law Gas Stoichiometry CHEMISTRY Matter and Change 13 Table Of Contents Chapter 13: Gases Section 13.1 Section 13.2 Section 13.3 The Gas Laws The Ideal Gas Law Gas Stoichiometry State the relationships among pressure, temperature,

More information

Exam 4 Practice Problems false false

Exam 4 Practice Problems false false Exam 4 Practice Problems 1 1. Which of the following statements is false? a. Condensed states have much higher densities than gases. b. Molecules are very far apart in gases and closer together in liquids

More information

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) 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

More information

Lecture Notes: Gas Laws and Kinetic Molecular Theory (KMT).

Lecture Notes: Gas Laws and Kinetic Molecular Theory (KMT). CHEM110 Week 9 Notes (Gas Laws) Page 1 of 7 Lecture Notes: Gas Laws and Kinetic Molecular Theory (KMT). Gases Are mostly empty space Occupy containers uniformly and completely Expand infinitely Diffuse

More information

Boyles Law. At constant temperature the volume occupied by a fixed amount of gas is inversely proportional to the pressure on the gas 1 P = P

Boyles Law. At constant temperature the volume occupied by a fixed amount of gas is inversely proportional to the pressure on the gas 1 P = P Boyles Law At constant temperature the volume occupied by a fixed amount of gas is inversely proportional to the pressure on the gas 1 or k 1 Boyles Law Example ressure olume Initial 2.00 atm 100 cm 3

More information

AS1 MOLES. oxygen molecules have the formula O 2 the relative mass will be 2 x 16 = 32 so the molar mass will be 32g mol -1

AS1 MOLES. oxygen molecules have the formula O 2 the relative mass will be 2 x 16 = 32 so the molar mass will be 32g mol -1 Moles 1 MOLES The mole the standard unit of amount of a substance the number of particles in a mole is known as Avogadro s constant (L) Avogadro s constant has a value of 6.023 x 10 23 mol -1. Example

More information

Chemistry 110 Lecture Unit 5 Chapter 11-GASES

Chemistry 110 Lecture Unit 5 Chapter 11-GASES Chemistry 110 Lecture Unit 5 Chapter 11-GASES I. PROPERITIES OF GASES A. Gases have an indefinite shape. B. Gases have a low density C. Gases are very compressible D. Gases exert pressure equally in all

More information

5. Which temperature is equal to +20 K? 1) 253ºC 2) 293ºC 3) 253 C 4) 293 C

5. Which temperature is equal to +20 K? 1) 253ºC 2) 293ºC 3) 253 C 4) 293 C 1. The average kinetic energy of water molecules increases when 1) H 2 O(s) changes to H 2 O( ) at 0ºC 3) H 2 O( ) at 10ºC changes to H 2 O( ) at 20ºC 2) H 2 O( ) changes to H 2 O(s) at 0ºC 4) H 2 O( )

More information

1.4.6-1.4.8 Gas Laws. Heat and Temperature

1.4.6-1.4.8 Gas Laws. Heat and Temperature 1.4.6-1.4.8 Gas Laws Heat and Temperature Often the concepts of heat and temperature are thought to be the same, but they are not. Perhaps the reason the two are incorrectly thought to be the same is because

More information

F321 MOLES. Example If 1 atom has a mass of 1.241 x 10-23 g 1 mole of atoms will have a mass of 1.241 x 10-23 g x 6.02 x 10 23 = 7.

F321 MOLES. Example If 1 atom has a mass of 1.241 x 10-23 g 1 mole of atoms will have a mass of 1.241 x 10-23 g x 6.02 x 10 23 = 7. Moles 1 MOLES The mole the standard unit of amount of a substance (mol) the number of particles in a mole is known as Avogadro s constant (N A ) Avogadro s constant has a value of 6.02 x 10 23 mol -1.

More information

Gases. States of Matter. Molecular Arrangement Solid Small Small Ordered Liquid Unity Unity Local Order Gas High Large Chaotic (random)

Gases. States of Matter. Molecular Arrangement Solid Small Small Ordered Liquid Unity Unity Local Order Gas High Large Chaotic (random) Gases States of Matter States of Matter Kinetic E (motion) Potential E(interaction) Distance Between (size) Molecular Arrangement Solid Small Small Ordered Liquid Unity Unity Local Order Gas High Large

More information

Chapter 13 Gases. Review Skills

Chapter 13 Gases. Review Skills Chapter 13 Gases t s Monday morning, and Lilia is walking out of the chemistry building, thinking about the introductory lecture on gases that her instructor just presented. Dr. Scanlon challenged the

More information

Gases and Kinetic-Molecular Theory: Chapter 12. Chapter Outline. Chapter Outline

Gases and Kinetic-Molecular Theory: Chapter 12. Chapter Outline. Chapter Outline Gases and Kinetic-Molecular heory: Chapter Chapter Outline Comparison of Solids, Liquids, and Gases Composition of the Atmosphere and Some Common Properties of Gases Pressure Boyle s Law: he Volume-Pressure

More information

87 16 70 20 58 24 44 32 35 40 29 48 (a) graph Y versus X (b) graph Y versus 1/X

87 16 70 20 58 24 44 32 35 40 29 48 (a) graph Y versus X (b) graph Y versus 1/X HOMEWORK 5A Barometer; Boyle s Law 1. The pressure of the first two gases below is determined with a manometer that is filled with mercury (density = 13.6 g/ml). The pressure of the last two gases below

More information

Problem Solving. Stoichiometry of Gases

Problem Solving. Stoichiometry of Gases Skills Worksheet Problem Solving Stoichiometry of Gases Now that you have worked with relationships among moles, mass, and volumes of gases, you can easily put these to work in stoichiometry calculations.

More information

2. The percent yield is the maximum amount of product that can be produced from the given amount of limiting reactant.

2. The percent yield is the maximum amount of product that can be produced from the given amount of limiting reactant. UNIT 6 stoichiometry practice test True/False Indicate whether the statement is true or false. moles F 1. The mole ratio is a comparison of how many grams of one substance are required to participate in

More information

Mole Notes.notebook. October 29, 2014

Mole 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 information

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. General Chemistry PHS 1015 Practice Exam 4 Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Which of the following statements about pressure

More information

Chem 1A Exam 2 Review Problems

Chem 1A Exam 2 Review Problems Chem 1A Exam 2 Review Problems 1. At 0.967 atm, the height of mercury in a barometer is 0.735 m. If the mercury were replaced with water, what height of water (in meters) would be supported at this pressure?

More information

Name Date Class STOICHIOMETRY. SECTION 12.1 THE ARITHMETIC OF EQUATIONS (pages 353 358)

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.

More information

The 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. 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 information

CHEM 120 Online Chapter 7

CHEM 120 Online Chapter 7 CHEM 120 Online Chapter 7 Date: 1. Which of the following statements is not a part of kinetic molecular theory? A) Matter is composed of particles that are in constant motion. B) Particle velocity increases

More information

Chapter 10. Can You... 1. draw the Lewis structure for a given covalently bonded molecule?

Chapter 10. Can You... 1. draw the Lewis structure for a given covalently bonded molecule? Chapter 10 Can You... 1. draw the Lewis structure for a given covalently bonded molecule? e.g. SF 6 and CH 3 Cl 2. identify and count the number of non-bonding and bonding domains within a given covalently

More information

Review - After School Matter Name: Review - After School Matter Tuesday, April 29, 2008

Review - After School Matter Name: Review - After School Matter Tuesday, April 29, 2008 Name: Review - After School Matter Tuesday, April 29, 2008 1. Figure 1 The graph represents the relationship between temperature and time as heat was added uniformly to a substance starting at a solid

More information

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) 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

More information

Gases. Macroscopic Properties. Petrucci, Harwood and Herring: Chapter 6

Gases. Macroscopic Properties. Petrucci, Harwood and Herring: Chapter 6 Gases Petrucci, Harwood and Herring: Chapter 6 CHEM 1000A 3.0 Gases 1 We will be looking at Macroscopic and Microscopic properties: Macroscopic Properties of bulk gases Observable Pressure, volume, mass,

More information

CHEMISTRY II FINAL EXAM REVIEW

CHEMISTRY II FINAL EXAM REVIEW Name Period CHEMISTRY II FINAL EXAM REVIEW Final Exam: approximately 75 multiple choice questions Ch 12: Stoichiometry Ch 5 & 6: Electron Configurations & Periodic Properties Ch 7 & 8: Bonding Ch 14: Gas

More information

Chemical Changes. Measuring a Chemical Reaction. Name(s)

Chemical Changes. Measuring a Chemical Reaction. Name(s) Chemical Changes Name(s) In the particle model of matter, individual atoms can be bound tightly to other atoms to form molecules. For example, water molecules are made up of two hydrogen atoms bound to

More information

Chapter 4 Practice Quiz

Chapter 4 Practice Quiz Chapter 4 Practice Quiz 1. Label each box with the appropriate state of matter. A) I: Gas II: Liquid III: Solid B) I: Liquid II: Solid III: Gas C) I: Solid II: Liquid III: Gas D) I: Gas II: Solid III:

More information

Gases. Solids' particles vibrate. This is the only motion experienced by this state of matter.

Gases. Solids' particles vibrate. This is the only motion experienced by this state of matter. 1. Kinetic Molecular Theory A. Main Points 1. All matter consists of particles: either atoms or molecules. For a gas, if it is monoatomic (like He or Ar), it will consist of atoms. If it consists of I2,

More information

Name Class Date. In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question.

Name Class Date. In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question. Assessment Chapter Test A Chapter: States of Matter In the space provided, write the letter of the term or phrase that best completes each statement or best answers each question. 1. The kinetic-molecular

More information

Name Class Date. F 2 2269 N A 1 88.12 cm 2 A 2 1221 cm 2 Unknown: Step 2: Write the equations for Pascal s principle and pressure, force, and area.

Name Class Date. F 2 2269 N A 1 88.12 cm 2 A 2 1221 cm 2 Unknown: Step 2: Write the equations for Pascal s principle and pressure, force, and area. Skills Worksheet Math Skills Pascal s Principle After you study each sample problem and solution, work out the practice problems on a separate sheet of paper. Write your answers in the spaces provided.

More information

Module 5: Combustion Technology. Lecture 33: Combustion air calculation

Module 5: Combustion Technology. Lecture 33: Combustion air calculation 1 P age Module 5: Combustion Technology Lecture 33: Combustion air calculation 2 P age Keywords: Heat of combustion, stoichiometric air, excess air, natural gas combustion Combustion air calculation The

More information

Sample Problem (mole-mass)

Sample Problem (mole-mass) Name: KEY Class: Sample Problem (mole-mass) Potassium chlorate is sometimes decomposed in the laboratory to generate oxygen. What mass of KClO 3 do you need to produce 0.50 moles of O 2? 2 KClO 3 (s) 2

More information

EXPERIMENT 15: Ideal Gas Law: Molecular Weight of a Vapor

EXPERIMENT 15: Ideal Gas Law: Molecular Weight of a Vapor EXPERIMENT 15: Ideal Gas Law: Molecular Weight of a Vapor Purpose: In this experiment you will use the ideal gas law to calculate the molecular weight of a volatile liquid compound by measuring the mass,

More information

Unit 9 Stoichiometry Notes (The Mole Continues)

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

More information

Unit 3 Notepack Chapter 7 Chemical Quantities Qualifier for Test

Unit 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 information

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: 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

More information

11-1 Stoichiometry. Represents

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.

More information

Solution. Practice Exercise. Concept Exercise

Solution. 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 information

IB Chemistry. DP Chemistry Review

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

More information

Multiple Choice questions (one answer correct)

Multiple Choice questions (one answer correct) Mole Concept Multiple Choice questions (one answer correct) (1) Avogadro s number represents the number of atoms in (a) 12g of C 12 (b) 320g of sulphur (c) 32g of oxygen (d) 12.7g of iodine (2) The number

More information

EXPERIMENT 13: THE IDEAL GAS LAW AND THE MOLECULAR WEIGHT OF GASES

EXPERIMENT 13: THE IDEAL GAS LAW AND THE MOLECULAR WEIGHT OF GASES Name Section EXPERIMENT 13: THE IDEAL GAS LAW AND THE MOLECULAR WEIGHT OF GASES PRE-LABORATORY QUESTIONS The following preparatory questions should be answered before coming to lab. They are intended to

More information

Stoichiometry. What is the atomic mass for carbon? For zinc?

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

More information

HEAT UNIT 1.1 KINETIC THEORY OF GASES. 1.1.1 Introduction. 1.1.2 Postulates of Kinetic Theory of Gases

HEAT UNIT 1.1 KINETIC THEORY OF GASES. 1.1.1 Introduction. 1.1.2 Postulates of Kinetic Theory of Gases UNIT HEAT. KINETIC THEORY OF GASES.. Introduction Molecules have a diameter of the order of Å and the distance between them in a gas is 0 Å while the interaction distance in solids is very small. R. Clausius

More information

THE KINETIC THEORY OF GASES

THE KINETIC THEORY OF GASES Chapter 19: THE KINETIC THEORY OF GASES 1. Evidence that a gas consists mostly of empty space is the fact that: A. the density of a gas becomes much greater when it is liquefied B. gases exert pressure

More information

Balancing Chemical Equations

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

More information

Chapter 3: Stoichiometry

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

More information

CHEMICAL EQUILIBRIUM (ICE METHOD)

CHEMICAL EQUILIBRIUM (ICE METHOD) CHEMICAL EQUILIBRIUM (ICE METHOD) Introduction Chemical equilibrium occurs when opposing reactions are proceeding at equal rates. The rate at which the products are formed from the reactants equals the

More information

Chemistry 13: States of Matter

Chemistry 13: States of Matter Chemistry 13: States of Matter Name: Period: Date: Chemistry Content Standard: Gases and Their Properties The kinetic molecular theory describes the motion of atoms and molecules and explains the properties

More information

Page 2. Base your answers to questions 7 through 9 on this phase diagram

Page 2. Base your answers to questions 7 through 9 on this phase diagram 1. The normal boiling point of water is often depressed at high altitudes. Which of the following explains this phenomenon? t high altitudes, the lower atmospheric pressure equals the equilibrium water

More information

Unit 10A Stoichiometry Notes

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

More information

Stoichiometry Review

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

More information

DETERMINING THE MOLAR MASS OF CARBON DIOXIDE

DETERMINING THE MOLAR MASS OF CARBON DIOXIDE DETERMINING THE MOLAR MASS OF CARBON DIOXIDE PURPOSE: The goal of the experiment is to determine the molar mass of carbon dioxide and compare the experimentally determined value to the theoretical value.

More information

Chemical Calculations: Formula Masses, Moles, and Chemical Equations

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

More information

THE IDEAL GAS LAW AND KINETIC THEORY

THE IDEAL GAS LAW AND KINETIC THEORY Chapter 14 he Ideal Gas Law and Kinetic heory Chapter 14 HE IDEAL GAS LAW AND KINEIC HEORY REIEW Kinetic molecular theory involves the study of matter, particularly gases, as very small particles in constant

More information

CHEM 105 HOUR EXAM III 28-OCT-99. = -163 kj/mole determine H f 0 for Ni(CO) 4 (g) = -260 kj/mole determine H f 0 for Cr(CO) 6 (g)

CHEM 105 HOUR EXAM III 28-OCT-99. = -163 kj/mole determine H f 0 for Ni(CO) 4 (g) = -260 kj/mole determine H f 0 for Cr(CO) 6 (g) CHEM 15 HOUR EXAM III 28-OCT-99 NAME (please print) 1. a. given: Ni (s) + 4 CO (g) = Ni(CO) 4 (g) H Rxn = -163 k/mole determine H f for Ni(CO) 4 (g) b. given: Cr (s) + 6 CO (g) = Cr(CO) 6 (g) H Rxn = -26

More information

ESSAY. Write your answer in the space provided or on a separate sheet of paper.

ESSAY. Write your answer in the space provided or on a separate sheet of paper. Test 1 General Chemistry CH116 Summer, 2012 University of Massachusetts, Boston Name ESSAY. Write your answer in the space provided or on a separate sheet of paper. 1) Sodium hydride reacts with excess

More information

Other Stoich Calculations A. mole mass (mass mole) calculations. GIVEN mol A x CE mol B. PT g A CE mol A MOLE MASS :

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

More information

CHEMICAL REACTIONS AND REACTING MASSES AND VOLUMES

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

More information

Description of the Mole Concept:

Description 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 information

Study the following diagrams of the States of Matter. Label the names of the Changes of State between the different states.

Study the following diagrams of the States of Matter. Label the names of the Changes of State between the different states. Describe the strength of attractive forces between particles. Describe the amount of space between particles. Can the particles in this state be compressed? Do the particles in this state have a definite

More information

Chapter 8: Gases and Gas Laws.

Chapter 8: Gases and Gas Laws. 133 Chapter 8: Gases and Gas Laws. The first substances to be produced and studied in high purity were gases. Gases are more difficult to handle and manipulate than solids and liquids, since any minor

More information

Chemical Calculations: The Mole Concept and Chemical Formulas. AW Atomic weight (mass of the atom of an element) was determined by relative weights.

Chemical 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 information

Calculations with Chemical Formulas and Equations

Calculations with Chemical Formulas and Equations Chapter 3 Calculations with Chemical Formulas and Equations Concept Check 3.1 You have 1.5 moles of tricycles. a. How many moles of seats do you have? b. How many moles of tires do you have? c. How could

More information

Molar Mass of Butane

Molar Mass of Butane Cautions Butane is toxic and flammable. No OPEN Flames should be used in this experiment. Purpose The purpose of this experiment is to determine the molar mass of butane using Dalton s Law of Partial Pressures

More information

Unit 3: States of Matter Practice Exam

Unit 3: States of Matter Practice Exam Page 1 Unit 3: States of Matter Practice Exam Multiple Choice. Identify the choice that best completes the statement or answers the question. 1. Two gases with unequal masses are injected into opposite

More information

How To Calculate Mass In Chemical Reactions

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

More information

Chapter 4: Chemical and Solution Stoichiometry

Chapter 4: Chemical and Solution Stoichiometry Chapter 4: Chemical and Solution Stoichiometry (Sections 4.1-4.4) 1 Reaction Stoichiometry The coefficients in a balanced chemical equation specify the relative amounts in moles of each of the substances

More information

7. Gases, Liquids, and Solids 7.1 Kinetic Molecular Theory of Matter

7. Gases, Liquids, and Solids 7.1 Kinetic Molecular Theory of Matter 7. Gases, Liquids, and Solids 7.1 Kinetic Molecular Theory of Matter Kinetic Molecular Theory of Matter The Kinetic Molecular Theory of Matter is a concept that basically states that matter is composed

More information

CHAPTER 8: CHEMICAL COMPOSITION

CHAPTER 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 information

CSUS Department of Chemistry Experiment 8 Chem.1A

CSUS Department of Chemistry Experiment 8 Chem.1A EXPERIMENT #8 Name: PRE-LABORATORY ASSIGNMENT: Lab Section 1. The alkali metals are so reactive that they react directly with water in the absence of acid. For example, potassium reacts with water as follows:

More information

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question.

MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. Exam Name MULTIPLE CHOICE. Choose the one alternative that best completes the statement or answers the question. 1) Given: 4 NO2(g) + O2(g) 2 N2O5(g) ΔH = -110.2 kj find ΔH for N2O5(g) 2 NO2(g) + 1/2 O2(g).

More information

Mole Calculations Multiple Choice Review PSI Chemistry

Mole 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 information

UNIVERSITY OF VICTORIA CHEMISTRY 102 Midterm Test 1 January 31, 2014 5-6 pm (60 minutes) DISPLAY YOUR STUDENT ID CARD ON THE TOP OF YOUR DESK NOW

UNIVERSITY OF VICTORIA CHEMISTRY 102 Midterm Test 1 January 31, 2014 5-6 pm (60 minutes) DISPLAY YOUR STUDENT ID CARD ON THE TOP OF YOUR DESK NOW Version B UNIVERSITY OF VICTORIA CHEMISTRY 102 Midterm Test 1 January 31, 2014 5-6 pm (60 minutes) Version B DISPLAY YOUR STUDENT ID CARD ON THE TOP OF YOUR DESK NOW Answer all multiple choice questions

More information

Chapter 1 The Atomic Nature of Matter

Chapter 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 information

CHEMISTRY COMPUTING FORMULA MASS WORKSHEET

CHEMISTRY COMPUTING FORMULA MASS WORKSHEET CHEMISTRY COMPUTING FORMULA MASS WORKSHEET Directions: Find the formula mass of the following compounds. Round atomic masses to the tenth of a decimal place. Place your final answer in the FORMULA MASS

More information

Stoichiometry V = 9.98 L CO2. 34.0 ml H 2 SO 4 soln 6.0 mol H 2 SO. 1000 ml H 2 SO 4 soln. 2 mol CO = 0.408 mol CO 2 1 mol H 2 SO 4

Stoichiometry V = 9.98 L CO2. 34.0 ml H 2 SO 4 soln 6.0 mol H 2 SO. 1000 ml H 2 SO 4 soln. 2 mol CO = 0.408 mol CO 2 1 mol H 2 SO 4 Stoichiometry We cannot count molecules so instead we weigh them; however, it is etremely inconvenient to weigh gases. So, when adding gases to a reaction how do we measure the amount of gas? We use the

More information

Stoichiometry Exploring a Student-Friendly Method of Problem Solving

Stoichiometry Exploring a Student-Friendly Method of Problem Solving Stoichiometry Exploring a Student-Friendly Method of Problem Solving Stoichiometry comes in two forms: composition and reaction. If the relationship in question is between the quantities of each element

More information

Materials 10-mL graduated cylinder l or 2-L beaker, preferably tall-form Thermometer

Materials 10-mL graduated cylinder l or 2-L beaker, preferably tall-form Thermometer VAPOR PRESSURE OF WATER Introduction At very low temperatures (temperatures near the freezing point), the rate of evaporation of water (or any liquid) is negligible. But as its temperature increases, more

More information

What s in a Mole? Molar Mass

What s in a Mole? Molar Mass LESSON 10 What s in a Mole? Molar Mass OVERVIEW Key Ideas Lesson Type Lab: Groups of 4 Chemists compare moles of substances rather than masses because moles are a way of counting atoms. When considering

More information

2. ATOMIC, MOLECULAR AND EQUIVALENT MASSES

2. ATOMIC, MOLECULAR AND EQUIVALENT MASSES 2. ATOMIC, MOLECULAR AND EQUIVALENT MASSES INTRODUCTION: EQUIVALENT WEIGHT Since hydrogen is the lightest of all elements, it was chosen as a standard for determination of equivalent weights. On this basis,

More information

Enthalpy of Reaction and Calorimetry worksheet

Enthalpy of Reaction and Calorimetry worksheet Enthalpy of Reaction and Calorimetry worksheet 1. Calcium carbonate decomposes at high temperature to form carbon dioxide and calcium oxide, calculate the enthalpy of reaction. CaCO 3 CO 2 + CaO 2. Carbon

More information

CHEM 101/105 Numbers and mass / Counting and weighing Lect-03

CHEM 101/105 Numbers and mass / Counting and weighing Lect-03 CHEM 101/105 Numbers and mass / Counting and weighing Lect-03 Interpretation of Elemental Chemical Symbols, Chemical Formulas, and Chemical Equations Interpretation of an element's chemical symbol depends

More information

Introduction to the Ideal Gas Law

Introduction to the Ideal Gas Law Course PHYSICS260 Assignment 5 Consider ten grams of nitrogen gas at an initial pressure of 6.0 atm and at room temperature. It undergoes an isobaric expansion resulting in a quadrupling of its volume.

More information

General Chemistry I (FC, 09-10) Lab #3: The Empirical Formula of a Compound. Introduction

General Chemistry I (FC, 09-10) Lab #3: The Empirical Formula of a Compound. Introduction General Chemistry I (FC, 09-10) Introduction A look at the mass relationships in chemistry reveals little order or sense. The ratio of the masses of the elements in a compound, while constant, does not

More information

THE HUMIDITY/MOISTURE HANDBOOK

THE HUMIDITY/MOISTURE HANDBOOK THE HUMIDITY/MOISTURE HANDBOOK Table of Contents Introduction... 3 Relative Humidity... 3 Partial Pressure... 4 Saturation Pressure (Ps)... 5 Other Absolute Moisture Scales... 8 % Moisture by Volume (%M

More information

Online Changing States of Matter Lab Solids What is a Solid? 1. How are solids different then a gas or a liquid?

Online Changing States of Matter Lab Solids What is a Solid? 1. How are solids different then a gas or a liquid? Name: Period: Online Changing States of Matter Lab Solids What is a Solid? 1. How are solids different then a gas or a liquid? 2. What are the atoms doing in a solid? 3. What are the characteristics of

More information

The Mole. Chapter 2. Solutions for Practice Problems

The 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 information

Chapter 3. Chemical Reactions and Reaction Stoichiometry. Lecture Presentation. James F. Kirby Quinnipiac University Hamden, CT

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

More information

CHEM 36 General Chemistry EXAM #1 February 13, 2002

CHEM 36 General Chemistry EXAM #1 February 13, 2002 CHEM 36 General Chemistry EXAM #1 February 13, 2002 Name: Serkey, Anne INSTRUCTIONS: Read through the entire exam before you begin. Answer all of the questions. For questions involving calculations, show

More information