Name Date Class STATES OF MATTER. SECTION 13.1 THE NATURE OF GASES (pages )

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1 Name Date Class 3 SAES OF MAER SECION 3. HE NAURE OF GASES (pages ) his section introduces the kinetic theory and describes how it applies to gases. It defines gas pressure and explains how temperature is related to the kinetic energy of the particles of a substance. Kinetic heory and a Model for Gases (pages ). he energy an object has because of its motion is called kinetic energy.. Circle the letter of each sentence that is true about the assumptions of the kinetic theory concerning gases. a. A gas is composed of particles with insignificant volume that are relatively far apart from each other. b. Strong attractive forces exist between particles of a gas. c. Gases tend to collect near the bottom of a container. d. he paths of uninterrupted travel of particles in a gas are relatively short because the particles are constantly colliding with each other or with other objects. Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. 3. Is the following statement true or false? According to the kinetic theory, collisions between particles in a gas are perfectly elastic because kinetic energy is transferred without loss from one particle to another, and the total kinetic energy remains constant. true Gas Pressure (pages ) 4. Gas pressure results from the force exerted by a gas per unit surface area of an object. 5. Simultaneous collisions of billions of particles in a gas with an object result in gas pressure. 6. What force holds the particles of air in Earth s atmosphere? gravity 7. What kind of pressure is measured with a barometer? atmospheric pressure Chapter 3 States of Matter 37

2 Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. Name Date Class CHAPER 3, States of Matter (continued) 8. Look at Figure 3. on page 386. What accounts for the difference in height of the two mercury columns shown in the figure? he mercury column on the left is shown at sea level; the one on the right is shown at an altitude of 9000 m. Because atmospheric pressure decreases as altitude increases, the column on the right is lower than the one on the left. 9. Circle the letter next to every name of a unit of pressure. a. mm Hg d. kpa b. standard e. atm c. pascal f. degree 0. Standard temperature and pressure (SP) are defined as a temperature of 0 C and a pressure of 0.3 kpa or atm Kinetic Energy and emperature (pages ). What happens to the temperature of a substance when the average kinetic energy of its particles increases? he temperature of the substance increases.. Is the following statement true or false. All the particles in a substance at a given temperature have the same kinetic energy. false 3. he temperature 0K, or 73.5 C, is called kinetic energy zero. heoretically, particles of matter at this temperature would have no. kinetic energy/motion 4. On the graph below, write the labels lower temperature and higher temperature to identify the curve that depicts the kinetic energy distribution of particles in a liquid at a lower temperature and at a higher temperature. lower temperature Percent of molecules higher temperature Kinetic energy 38 Guided Reading and Study Workbook

3 Name Date Class 5. Circle the letter of the temperature scale that correctly completes this sentence. emperature on the scale is directly proportional to the average kinetic energy of the particles of a substance. a. Celsius b. Kelvin c. Fahrenheit d. Centigrade SECION 3. HE NAURE OF LIQUIDS (pages ) his section describes a model for liquids in terms of kinetic energy and the attractive forces between the particles in a liquid. It also uses kinetic theory to distinguish evaporation from boiling. A Model for Liquids (page 390). Is the following sentence true or false? he kinetic theory states that there are no attractions between the particles of a liquid. false. Circle the letter next to each sentence that is true about the particles of a liquid. a. Most of the particles in a liquid have enough kinetic energy to escape into a gaseous state. Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. b. Liquids are much denser than gases because intermolecular forces reduce the amount of space between the particles in a liquid. c. Increasing pressure on a liquid has hardly any effect on its volume. d. Liquid particles are free to slide past one another. Evaporation (page 39) 3. he conversion of a liquid to a gas or vapor is called vaporization. 4. When vaporization occurs at the surface of a liquid that is not boiling, the process is called evaporation. 5. As a liquid evaporates, why do only some of the particles break away from the surface of the liquid? Why does the liquid evaporate faster if the temperature is increased? Most of the molecules do not have enough kinetic energy to overcome the attractive forces. As the temperature is increased, the average kinetic energy increases and more particles have enough kinetic energy to overcome the forces keeping them in the liquid state. Chapter 3 States of Matter 39

4 Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. Name Date Class CHAPER 3, States of Matter (continued) 6. Is the following sentence true or false? Evaporation is a cooling process because the particles in a liquid with the highest kinetic energy tend to escape first, leaving the remaining particles with a lower average kinetic energy and, thus, a lower temperature. true Questions 7, 8, 9, and 0 refer to either container A or container B below. hink of each container as a system involving both liquid water and water vapor. (a) (b) 7. From which of the containers are water molecules able to escape? b 8. In which container can a dynamic equilibrium between water molecules in the liquid state and water molecules in the vapor state be established? a 9. In which container will the water level remain constant? a 0. From which container is it possible for all of the liquid water to disappear through evaporation? b. What causes the chill you may feel after stepping out of a swimming pool on a warm, windy day? Wind causes water on the skin to evaporate, which is a cooling process. 40 Guided Reading and Study Workbook

5 Name Date Class Vapor Pressure (pages ). Circle the letter next to each sentence that is true about vapor pressure. a. Vapor pressure arises when particles of a liquid in a closed, partly filled container vaporize and collide with the walls of the container. b. After a time in a closed, partly filled container, a liquid will evaporate and its vapor will condense at equal rates. c. Look at Figure 3.6b on page 39. Condensation on the inside of the terrarium indicates that there is not a liquid-vapor equilibrium in the sealed terrarium. d. When the temperature of a contained liquid increases, its vapor pressure increases. 3. Look at Figure 3.7 on page 393. How does the vapor pressure of the ethanol in the manometer change when the temperature is increased from 0 C to 0 C? Circle the letter of the correct answer. a. he vapor pressure decreases by more than 4 kpa. b. he vapor pressure remains constant. c. he vapor pressure increases by more than 4 kpa. d. here is no way to detect a change in vapor pressure with a manometer. Boiling Point (pages ) Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. 4. he boiling point of a liquid is the temperature at which the vapor pressure of the liquid is just equal to the external pressure. 5. Look at Figure 3.8 on page 394. Why does the boiling point decrease as altitude increases? At higher altitudes, atmospheric pressure is lower than it is at sea level. Because boiling occurs when vapor pressure is equal to atmospheric pressure, a liquid boils at a lower temperature. 6. Use Figure 3.9 on page 394. At approximately what temperature would ethanol boil atop Mount Everest, where the atmospheric pressure is 34 kpa? Circle the letter next to the best estimate. a. 50 C b. 00 C c. 0 C d. 85 C 7. Is the following sentence true or false? After a liquid reaches its boiling point, its temperature continues to rise until all the liquid vaporizes. false Chapter 3 States of Matter 4

6 Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. Name Date Class CHAPER 3, States of Matter (continued) Reading Skill Practice Writing a summary can help you remember what you have read. When you write a summary, include only the most important points. Write a summary of the discussion of boiling point on pages Do your work on a separate sheet of paper. Students summaries should include a definition of boiling point and normal boiling point. hey should also include the effects of pressure on the temperature of a boiling liquid. SECION 3.3 HE NAURE OF SOLIDS (pages ) his section describes the highly organized structures of solids, distinguishes between a crystal lattice and a unit cell, and explains how allotropes of an element differ. A Model for Solids (page 396). Is the following sentence true or false? Although particles in solids have kinetic energy, the motion of particles in solids is restricted to vibrations about fixed points. true. A solid melts when. the organization of its particles breaks down 3. Is the following sentence true or false? he temperature at which the liquid and solid states of a substance are in equilibrium is the same as the melting point and the freezing point of the substance. true Crystal Structure and Unit Cells (pages ) 4. How are particles arranged in a crystal? hey are arranged in an orderly, repeating, three-dimensional pattern. 5. What type of solid has a relatively low melting point? A molecular solid has a relatively low melting point. 6. Do all solids melt when heated? Explain. No; some solids, such as wood, decompose. 7. Circle the letter next to each sentence that is true about solids. a. Most solid substances are not crystalline. b. All crystals have sides, or faces, that intersect at angles that are characteristic for a given substance. c. here are seven groups, or crystal systems, into which all crystals may be classified. d. he orderly array of sodium ions and chloride ions gives crystals of table salt their regular shape. 4 Guided Reading and Study Workbook

7 Name Date Class Identify the unit cell in each figure below as simple cubic, body-centered cubic, or face-centered cubic. 8. face-centered cubic 9. body-centered cubic 0. simple cubic. Is the following sentence true or false? Some solid substances can exist in more than one form. Give an example to support your answer. rue. he element carbon has at least three solid forms: graphite, diamond, and buckminsterfullerene.. wo or more different molecular forms of the same element in the same physical state are called allotropes. 3. What is an amorphous solid? An amorphous solid lacks an ordered internal structure. 4. Circle the letter next to each solid that is an amorphous solid. a. table salt c. plastic Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. b. rubber d. glass 5. How are glasses different from crystalline solids? he internal structures of glasses are intermediate between free-flowing liquids and crystalline solids. Glasses do not have a definite melting point, but soften when heated. Glass breaks into irregular, jagged pieces when shattered. SECION 3.4 CHANGES OF SAE (pages ) his section describes the process of sublimation. It also explains phase changes between solid, liquid, and vapor states and how to interpret a phase diagram. Sublimation (page 40). he process by which wet laundry dries on an outdoor clothesline in winter is called sublimation.. Is the following sentence true or false? Solids have vapor pressure because some particles near the surface of a solid substance have enough kinetic energy to escape directly into the vapor phase. true Chapter 3 States of Matter 43

8 Pearson Education, Inc., publishing as Pearson Prentice Hall. All rights reserved. Name Date Class CHAPER 3, States of Matter (continued) Phase Diagrams (pages ) 3. What does a phase diagram show? A phase diagram shows the temperature and pressure conditions at which a substance exists in the solid, liquid, and vapor phases. 4. What is the triple point of a substance? he triple point represents the only conditions of temperature and pressure at which three phases of a substance can exist in equilibrium. 5. In the phase diagram for water shown below, label the melting point and boiling point at normal atmospheric pressure, and the triple point. Normal boiling point Normal melting point Pressure (kpa) Solid Liquid Vapor riple point emperature ( C) 6. Use the phase diagram above to answer the following question. Why is a laboratory required to produce the conditions necessary for observing water at the triple point? From the diagram, the triple point of water is at a pressure of 0.6 kpa, far below atmospheric pressure. Laboratory equipment is necessary to achieve pressures this low. 44 Guided Reading and Study Workbook

9 . What causes air pressure in a closed container?. What is the speed of gas particles? 3. What is the distance between gas particles? 4. What happens when gas particles collide with each other?. Read pages Ben has a deflated soccer ball. He takes a hand pump and pumps it up.. What happens to the number of particles in the ball?. Would the pressure increase, decrease, stay the same? 3. If Ben puts in twice as many particles, would the pressure increase, decrease, stay the same? By how much?

10 Name 4. Rose buys a small canister of compressed helium gas to fill balloons for a party. She decides she wants a really large balloon, so she keeps adding helium to the balloon. What do you predict will happen to the balloon? Why? 5. he canister of helium gas is not very large but she can fill about fifty 9 inch balloons. Compare the volume of the canister of gas with the volume of the 50 balloons. 6. After several days, the helium balloons are almost deflated. What is happening? 7. As a demonstration for chemistry class, the chemistry teacher inserts a balloon into a large container of liquid nitrogen (-96 Cº). What happens to the volume of the balloon? Why? You can buy a can of Office Duster 3. he can holds 0 ounces of a pressurized gas. he company decides to sell a 0 ounce pray can. he pressure will remain the same as the smaller can. 8. What will the volume of the can have to be? 9. Why does the gas in the can leave the can when the nozzle is depressed? (Hint; think of high pressure versus low pressure.)

11 0. You use the Office Duster 3 to remove the dust on your computer keyboard, what happens to the pressure in the can?. Is the can empty when no more gas is released when the nozzle is depressed? Why or why not?. When the gas is released from the can, why does it feel cold? 3. he instructions on the can say, Do not puncture container. Why this warning? 4. he instructions also say, Do not incinerate. Why this warning? 5. he can also says Do not expose to heat, use near open flame, or store at temperatures over 0ºF. Store in a cool place out of direct sunlight. What could happen if the can was left in a car parked in the sun on a July day when the temperature is in the 90 s?

12 Boyle s Law Chem Worksheet 4- Name Robert Boyle observed the relationship between the pressure and volume for a gas sample. hese two variables are inversely proportional. his means that when the pressure goes up the volume goes down. his is expressed in the equation P V = P V, which is known as Boyle s Law. he relationship between pressure and volume is only observed when the temperature and amount of gas particles do not change. he graph below shows this relationship. Volume (ml) Boyle's Law USEFUL EQUAIONS P V = P V.00 atm = 760 mmhg.00 atm = 0300 Pa.00 atm = 760 torr.00 atm = 0.3 kpa.00 atm = 4.7 psi Pressure (atm) example A gas occupies a volume of 5.4 L at a pressure of.06 atm. What volume will the gas occupy if when the pressure is increased to.5 atm? Assume the temperature does not change. - list the variables: V = 5.4 L P =.06 atm P =.5 atm - substitute into the equation: P V = P V (.06 atm) (5.4 L) = (.5 atm) V - solve: (.06 atm) (5.4 L) (.5 atm) V =.5 atm.5 atm V = 3.8 L Solve the following problems.. According to the graph, when the pressure of a gas sample is decreased what happens to the volume?. he gas in a 600 ml balloon has a pressure of.0 atm. If the temperature remains constant, what will be the pressure of the gas in the balloon when it is compressed to 400 ml? 3. An oxygen container has a volume of 48 ml and a pressure of 40 kpa. What is the volume of this gas when the pressure is 05 kpa? 4. A tank of compressed CO has a pressure of 850 psi and a volume of 50 ml. What is the volume of this gas when the pressure is 45 psi? 5. A scuba tank has a pressure of 9,300 kpa and a volume of 0.3 L. What would be the pressure of the gas if it were transferred to a 50.0 L container? 6. Air fills a room with a volume of 5600 L. Atmospheric pressure is 740 torr. What will be the pressure if all of the gas is pumped into an 80 L tank? Convert this pressure to kpa. 7. A sample of 4 L of helium gas is stored in a cylinder at a pressure of 0 lb/in. he helium is transferred to a container with a volume of 5 L. Assuming the temperature has not changed what will be the pressure? 8. An air compressor has a volume of 0 L. What volume of gas is pumped into the tank if the pressure goes from 750 torr to a pressure of 45 psi? John Erickson, 005 WS4-BoylesLaw

13 Charles Law Chem Worksheet 4- Name Jacques Charles made the observation the volume of a gas is directly proportional to the Kelvin temperature of the gas. If the Kelvin temperature is doubled, the volume also doubles. he equation for this relationship is V V =, where V represents volume and represents temperature. he volume of a gas can be measured in liters, milliliters, cubic meters, or a variety of other units, but the temperature Charles' Law must be converted to kelvins. his relationship is only 40 observed when the pressure remains constant USEFUL EQUAIONS Volume (L) emperature (K) V V = K = C + 73 ml = cm 3 5 ( 3) L = 000 ml c = f 9 example A gas sample with a volume of 35 ml is heated from 5ºC to 45ºC. What is the new volume? Assume a constant pressure. - list the variables: V = 35 ml = 5ºC = 98 K = 45ºC = 698 K - substitute into the equation: V = V 35 ml V = 98 K 698 K - solve by cross-multiplying: ( 35 ml) (698 K) = V (98 K) ( 35 ml) (698K) (98K) = V V 98K 98K ml = 8 Solve the following problems. Assume that the pressure does not change.. According to the graph, when the Kelvin temperature of a gas is doubled, what happens to the volume?. Using the graph, estimate the Kelvin temperature that the gas sample would reach a volume of 40 L. 3. A 40 ml sample of argon gas at 70 K is cooled until the volume is 80 ml. What is the new temperature? 4. A container of oxygen with a volume of 60 L is heated from 300 K to 400 K. What is the new volume? 5. When a piston with a volume of 35 ml is heated from 5ºC to 33ºC it expands. Assuming the pressure on the piston remains the same, determine the new volume of the cylinder. 6. A balloon with a volume of 5.3 L is taken from an indoor temperature of 4ºC to the outdoors. he volume of the balloon outside is 4.9 L. Determine the Celsius temperature outside. 7. A movable piston contains a sample of 680 ml of neon gas with a temperature of -5ºC. When the piston is heated the sample expands to a volume of.3 L. What is the new temperature of the neon gas? 8. A helium balloon has a volume of 600 cm 3 when the temperature is ºC. What is the volume of the balloon when it s placed in a freezer with a temperature of -5ºC? 9. he Kelvin temperature of sample of 650 cm 3 sample of ammonia gas is doubled. What is the new volume of the gas? Assume that the pressure stays constant. 0. A movable piston is allowed to cool from 39ºF to 04ºF. If the initial volume is 05 ml, what will be the new volume? John Erickson, 005 WS4-CharlesLaw

14 Gay-Lussac s Law. What is Gay-Lussac s Law?. A gas has a pressure of 6.58 kpa at 539 K. What will be the pressure at K? Volume is constant. 3. A gas with a pressure of.00 x0 3 kpa at 0.0 C is heated until its temperature is 50.0 C. What is the new pressure? 4. Determine the pressure change when a constant volume of gas at 0.3 kpa is heated from 0.0 C to 30.0 C. 5. A gas has a pressure of 37.5 kpa at 50.0 C. What is the pressure at standard temperature? 6. A gas has a pressure of 05.6 kpa Hg at 40.0 C. What is the temperature at standard pressure? 7. If a gas is cooled from 33.0 K to 73.5 K and the volume is kept constant what final pressure would result if the original pressure was 99.9 kpa? 8. If a gas in a closed container is pressurized from 50 kpa to 6 kpa and its original temperature was 5.0 C, what would the final temperature of the gas be? 9. A 30.0 L sample of nitrogen inside a rigid, metal container at 0.0 C is placed inside an oven whose temperature is 50.0 C. he pressure inside the container at 0.0 C was at kpa. What is the pressure of the nitrogen after its temperature is increased?

15 Combined Gas Law Chem Worksheet 4-3 Name Boyle s law shows that the pressure and volume of a gas are inversely related. Charles law shows that the kelvin temperature and volume of a gas are directly related. hese two relationships can be combined into a single equation known as the combined gas law. he formula for the combined gas law PV P V is: = his equation could be memorized instead of memorizing Boyle s law, Charles law, and Law Equation Constant Variable Boyle s Law PV = temperature P V Guy-Lussac s law. Each of these other gas laws can be derived from the combined gas law by canceling out the variable that does not change. Charles Law Guy-Lussac s Law PV = pressure PV P V = volume P V PV USEFUL EQUAIONS P V = K = C + 73 example A 8 L sample of gas has a pressure of 5 psi when the temperature is 45ºC. What is the volume of the gas if the pressure is increased to 75 psi and the temperature is increased to 30ºC? - list the variables: V = 8 L P = 5 psi = 45ºC = 33 K V =? P = 75 psi = 30ºC = 593 K - substitute into the equation: PV PV = ( 5 psi)(8 L) (75 psi)( V ) = (33 K) (593 K) - cross-multiply and simplify: 5 psi)(8 L) (593 K) = (75 psi) ( V )(33 K) ( ( 5 psi)(8 L)(593 K) (75 psi)( V )(33 K) = (75 psi) (33 K) (75 psi)(33 K) - solve: V = 7.6 L Solve the following problems.. A canister containing air has a volume of 85 cm 3 and a pressure of.45 atm when the temperature is 30 K. What is the pressure when the volume is increased to 80 cm 3 and the temperature is reduced to 80 K?. Air is transferred from a 75 L tank where the pressure is 5 psi and the temperature is 88 K to a tire with a volume of 6. L and a pressure of 5 psi. What is the new temperature? 3. A helium balloon at 8ºC has a volume of.8 L and a pressure of 0 kpa. What is the volume of the balloon when is rises into the atmosphere where the pressure is 85 kpa and the temperature is 4ºC? 4. he pressure of a piston with a volume of 650 cm 3 and 85ºC is 830 torr. It is heated to 350ºC and compressed to a volume of 65 cm 3. What is the new pressure? 5. A gas tank has a volume of 8. m 3 and a pressure of 8.4 atm. he temperature of the gas is 3ºC. What is the Celsius temperature when the gas is put in an. m 3 tank with a pressure of.7 atm? 6. A metal can is able to withstand 3800 kpa before is bursts. he gas in the can has a volume of 35 ml and the pressure is 0 kpa at 5ºC. If the can is crushed to a volume of 8.5 ml and the temperature does not change will it burst? What is the pressure of the gas in the can? John Erickson, 005 WS4-3CombinedGasLaw

16 Ideal Gas Law Chem Worksheet 4-4 Name he ideal gas law is an equation that relates the volume, temperature, pressure and amount of gas particles to a constant. he ideal gas constant is abbreviated with the variable R and has the value of 0.08 atm L/mol K. he ideal gas law can be used when three of the four gas variables are known. When using this equation it is important that the units for pressure are atmospheres (atm), volume is in liters (L), and temperature is converted to kelvins (K). he amount of gas is measured in units called moles (mol). Unknown Equation Known Variables USEFUL EQUAIONS PV = nr.00 atm = 0300 Pa atm L R = 0.08 mol K.00 atm = 0.3 kpa K = C atm = 760 mmhg cm 3 = ml.00 atm = 760 torr L = 000 ml.00 atm = 4.7 psi pressure volume temperature nr P = V nr V = P PV = nr amount, temp., volume amount, temp., pressure pressure, volume, amount amount PV n = R pressure, volume, temp. example he pressure exerted by.8 moles of argon gas at a temperature of 85ºC is 40 torr. What is the volume of this sample? - list the variables: P = 40 torr V =? n =.8 mol R = 0.08 = 85ºC atm L mol K - convert the variables: 40 torr atm = atm = 85ºC + 73 = 358 K 760 torr - substitute into the equation: nr V = P atm L (.8 mol)( )(358 K) mol K V = = 8 L atm Solve the following problems.. A tank contains 5 moles of neon gas. It has a pressure of 57 atm at a temperature of 45ºC. Calculate the volume of the tank.. A scuba tank has a pressure of 95 atm at a temperature of 0ºC. he volume of the tank is 350 L. How many moles of air are in the tank? 3. A helium-filled balloon has a volume of 08 L and it contains 9.95 moles of gas. If the pressure of the balloon is.6 atm, determine the temperature in Celsius degrees. 4. A tank of oxygen has a volume of 650 L. he temperature of the gas inside is 35ºC. If there are 9750 moles of oxygen in the tank what is the pressure in PSI? 5. A canister of acetylene has a volume of 4 L. he temperature of the acetylene is 305 K and the pressure is 780 torr. Determine the amount (moles) of gas in the canister. 6. Calculate the volume of a CO cartridge that has a pressure of 850 PSI at a temperature of ºC. he cartridge contains 0.73 mol of CO. 7. A tank contains 500 L of argon gas. he pressure is3790 kpa and the temperature is 5ºC. How many moles of argon are in the tank? John Erickson, 005 WS4-4IdealGasLaw

17 Partial Pressures of Gas Chem Worksheet 4-6 Name Dalton s law of partial pressures states that the total pressure of a mixture of gases is equal to the sum of the individual pressures. In other words, mixtures of gases behave the same as a single gas would. In a mixture of gases each individual gas contributes its own pressure, known as the partial pressure, to the total pressure. he pressure of each gas is determined by the number of moles of gas, its volume and temperature. he sum of each gas pressure equals to the total pressure. he equation for this law is P total = P + P + P P n USEFUL EQUAIONS.00 atm = 760 torr PV = nr R = 0.08 atm L mol K Solve the following problems.. A canister contains 45 kpa of carbon dioxide, 750 kpa of nitrogen, and 55 kpa of oxygen. What is the total pressure of the container?. A tank containing ammonia and argon has a total pressure equal to.8 atm. he pressure of the ammonia is. atm. What is the pressure of the argon gas? 3. A sample of gas contains 3 moles of argon and 5 moles of krypton. If the argon exerts a pressure of 0 torr, what is the pressure of the krypton? What is the total pressure? A 3.6 ml sample of hydrogen gas is collected over water using a technique known as water displacement. he temperature of the gas is 95 K. he total pressure of the mixture (hydrogen and water vapor) is 785. torr. 4. At 95 K the vapor pressure of water is 9.8 torr. Find the pressure of the hydrogen gas alone. 5. Using the volume and temperature given above, calculate the number of moles of hydrogen present. 6. Using the volume and temperature above, determine the number of moles of water vapor present. he tank shown below contains helium, nitrogen, and oxygen gas and it has a volume of 45 L. Each marker in the container represents a mole of gas in the mixture. he container is at room temperature (0ºC). 7. Count the number of moles of helium in the sample. Repeat for nitrogen and oxygen. 8. Determine the fraction of each of the three gases. helium nitrogen oxygen 9. Calculate the pressure of each gas. Use the volume and temperature listed above for each calculation. 0. Find the total pressure inside the container by adding the partial pressures for each gas. John Erickson, 005 WS4-6PartialPressures

18 Gas Stoichiometry Chem Worksheet 4-5 Name Use your knowledge of Stoichiometry and the Ideal Gas Law to solve the following problems. he chemical equations given are all balanced.. What volume of O is produced when 8.5 g of hydrogen peroxide (H O ) decomposes to form water and oxygen at 50 C and.0 atm? H O (aq) H O (l) + O (g) 5. At what pressure is the nitrogen gas sample that is collected when 48.4 g of NaN 3 decomposes? he temperature of the gas is 5 C and the volume is 8.4 L. NaN 3 (s) Na (s) + 3N (g). his reaction uses 8. g of copper (I) sulfide (Cu S). What volume of sulfur dioxide gas would be collected at 37 C and 0.7 atm? Cu S (s) + 3O (g) Cu O (s) + SO (g) 6. When.4-g zinc is added to hydrochloric acid, 450 ml of hydrogen gas forms at a temperature of 3 C. What is the pressure of the gas? Zn (s) + HCl (aq) ZnCl (aq) + H (g) 3. When 6.7-g nitrogen and excess oxygen react they generate nitrogen dioxide. If the NO is collected at 65 K and 0.74 atm, what volume will it occupy? N (g) + O (g) NO (g) 7. he following reaction forms 6.4 L of oxygen at a temperature of 8.7 C and a pressure of 73 torr, what mass of KClO 3 must have decomposed? KClO 3 (s) KCl (s) + 3O (g) 4. What volume of hydrogen gas is evolved from a reaction between 0.5 g of Na and water? he gas is collected at 0. C and 745 mmhg. Na (s) + H O (l) NaOH (aq) + H (g) 8. What mass of CaSO 3 must have been present initially to produce 4.5 L of SO gas at a temperature of.5 C and a pressure of.0 atm? CaSO 3 (s) CaO (s) + SO (g) Chemistry WS4-5GasStoich

19 Dalton s Law of Partial Pressures, Ideal Gas Law, Combined Gas Law, & Gas Stoich. A metal tank contains three gases: oxygen, helium, and nitrogen. If the partial pressures of the three gases in the tank are 35 atm of O, 5 atm of N, and 5 atm of He, what is the total pressure inside of the tank?. Blast furnaces give off many unpleasant and unhealthy gases. If the total air pressure is 0.99 atm, the partial pressure of carbon dioxide is 0.05 atm, and the partial pressure of hydrogen sulfide is 0.0 atm, what is the partial pressure of the remaining air? 3. If the air from problem contains % oxygen, what is the partial pressure of oxygen near a blast furnace? 4. If four moles of a gas at a pressure of 5.4 atmospheres have a volume of 0 liters, what is the temperature? 9

20 5. If I initially have a gas with a pressure of 84 kpa and a temperature of 350 ⁰C and I heat it an additional 30 degrees, what will the new pressure be? Assume the volume of the container is constant. 6. My car has an internal volume of 600 liters. If the sun heats my car from a temperature of 00 ⁰C to a temperature of 550 ⁰C, what will the pressure inside my car be? Assume the pressure was initially 760 mm Hg. 7. How many moles of gas are in my car in problem #3? 8. A toy balloon filled with air has an internal pressure of.5 atm and a volume of.50 L. If I take the balloon to the bottom of the ocean where the pressure is 95 atmospheres, what will the new volume of the balloon be? How many moles of gas does the balloon hold? (Assume = 85 K) 0

21 9. For the reaction H(g) + O(g) HO(g), how many liters of water can be made from 5 L of oxygen gas and an excess of hydrogen? 0. How many liters of water can be made from 55 grams of oxygen gas and an excess of hydrogen at SP?. How many liters of water can be made from 55 grams of oxygen gas and an excess of hydrogen at a pressure of.4 atm and a temperature of 850 C?. How many liters of water can be made from 34 grams of oxygen gas and 6.0 grams of hydrogen gas at SP? What is the limiting reactant for this reaction?

22 CHEMISRY GAS LAW S WORKSHEE 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 he volume of a fixed mass of gas is directly proportional to its Kelvin temperature if the pressure is kept constant. V = k he pressure of a gas is Combines Boyle s, directly proportional to Charles, and the the Kelvin temperature if emperature-pressure the volume is kept relationship into one constant. equation. Each of these laws can be derived from this law. P = k PV = k V = V P = P VP = VP PV = PV V = V P = P P V = P V Dalton s Law Ideal Gas Law Graham s Law At constant volume and temperature, the total pressure exerted by a mixture of gases is equal to the sum of the pressures exerted by each gas, he Ideal Gas Law relates the pressure, temperature, volume, and mass of a gas through the gas constant R. he rate of effusion/diffusion of two gases (A and B) are inversely proportional to the square roots of their formula masses. [It can be a ratio of molecular speeds, effusion /diffusion times, distance traveled by molecules, or amount of gas effused] P total = P + P + P P n PV = nr Rate A Rate B = molar mass B molar mass A Abbreviations atm = atmosphere mm Hg = millimeters of mercury torr = another name for mm Hg Pa = Pascal kpa = kilopascal K = Kelvin C = degrees Celsius Conversions K = C + 73 F o =.8C o + 3 C o = Fo 3.8 cm3 (cubic centimeter) = ml (milliliter) dm3 (cubic decimeter) = L (liter) = 000 ml Standard Conditions 0 C = 73 K.00 atm = mm Hg = 76 cm Hg =0.35 kpa = 0, 35 Pa = 9.9 in Hg Gas Law s Equation Symbols Subscript () = old condition or initial condition Subscript () = new condition or final condition emperature must be in Kelvins n = number of moles = grams/molar mass R = 8.3 L-kPa/ mol-k = 0.08 L-atm/mol-K = 6.4 L-orr/mol-K You must have a common set of units in the problem

23 CHEMISRY GAS LAW S WORKSHEE. Convert the following temperatures to K. a) 04 C b) -3 C. Convert the following temperatures to C. a) 67 K b) 67 K 3. A sample of nitrogen gas has a volume of 478 cm3 and a pressure of 04. kpa. What volume would the gas occupy at 88. kpa if the temperature remains constant? dm3 of hydrogen gas is collected at 38.8 C. Find the volume the gas will occupy at C if the pressure remains constant. 5. A sample of gas has a volume of 5 cm3 at 3.5 C and 84.6 kpa. What volume will the gas occupy at SP?

24 CHEMISRY GAS LAW S WORKSHEE 6. At a certain temperature, molecules of methane gas, CH4 have an average velocity of m/s. What is the average velocity of carbon dioxide molecules at this same temperature? 7. Find the relative rate of diffusion for the gases chlorine, Cl and ethane, CH cm3 of oxygen gas and 877 cm3 of nitrogen gas, both at 5.0 C and 4.7 kpa, are injected into an evacuated 536 cm3 flask. Find the total pressure in the flask, assuming the temperature remains constant. 9. A sample of gas is transferred from a 75 ml vessel to a ml vessel. If the initial pressure of the gas is 45 atm and if the temperature is held constant, what is the pressure of the gas sample in the ml vessel? 0. A sample of gas occupies a volume of ml at 740 mm Hg and 6 C. Determine the volume of this sample at 760 mm Hg and 37 C.

25 CHEMISRY GAS LAW S WORKSHEE. One mole of HS gas escapes from a container by effusion in 77 seconds. How long would it take one mole of NH3 gas to escape from the same container?. Convert a pressure of mm Hg to the equivalent pressure in pascals (Pa). 3. Air in a closed cylinder is heated from 5 C to 36 C. If the initial pressure is 3.80 atm, what is the final pressure? 4. A bubble of helium gas has a volume of ml near the bottom of a large aquarium where the pressure is.54 atm and the temperature is C. Determine the bubble s volume upon rising near the top where the pressure is.0 atm and 6 C. 5. At what temperature Celsius will 9.4 g of molecular oxygen, O, exert a pressure of 80 mm Hg in a 5. L cylinder?

26 CHEMISRY GAS LAW S WORKSHEE 6. A sample of nitrogen gas, N, is collected in a00 ml container at a pressure of 688 mm Hg and a temperature of 565 C. How many grams of nitrogen gas are present in this sample? 7. What is the pressure in mm of Hg, of a gas mixture that contains g of H, and 8.0 g of Ar in a 3.0 L container at 7 C. 8. o what temperature must 3.0 ft3 of a gas at C be heated for it to occupy.00 x 0 ft3 at the same pressure? 9. What is the pressure in atm exerted by.48 moles of a gas in a 50.0 ml container at 58 C? 0. Determine the molar mass of a gas that has a density of.8 g/l at 66 C and 70 mm Hg. (Hint: the number of moles of a substance is its mass/molecular mass and density is mass/volume.)