Deck 5: Matter and Heat

Question 1

The properties of several different materials are being compared.If the samples all have the same volume, the one with the greatest mass also has the greatest

A)density.
B)buoyancy.
C)pressure.
D)temperature.

Answer 1

density.

Question 2

Which of the following quantities is independent of the size and shape of an object composed of a given material?

A)volume
B)mass
C)weight
D)density

Answer 2

density

Question 3

A thermometer calibrated in the Celsius scale and a thermometer calibrated in the Fahrenheit scale are used to measure the same temperature.The numerical reading on the Fahrenheit thermometer

A)is proportional to that on the Celsius thermometer.
B)is smaller than that on the Celsius thermometer.
C)is larger than that on the Celsius thermometer.
D)may be smaller or larger than that on the Celsius thermometer.

Answer 3

may be smaller or larger than that on the Celsius thermometer.

Question 4

Buoyancy occurs because, as the depth in a fluid increases, the fluid's

A)pressure increases.
B)pressure decreases.
C)density increases.
D)density decreases.

Question 5

A Celsius thermometer and an absolute thermometer are used to measure the temperature of the same gas sample.The readings on the thermometers are respectively T_C and T_K.Which is correct?

A)T_C is smaller than T_K.
B)T_C is larger than T_K.
C)T_C is equal to T_K.
D)Any of these choices could be correct, depending on the gas temperature.

Question 6

In order for an object to sink when placed in water, the object's average density must be

A)less than that of water.
B)equal to that of water.
C)more than that of water.
D)Any of these choices are correct, depending on the object's shape.

Question 7

Heat can be transferred through a vacuum by which one or more of the following?

A)conduction
B)convection
C)radiation
D)condensation

Question 8

Of these substances, the one with the lowest specific heat is

A)water.
B)ice.
C)concrete.
D)gold.

Question 9

The pressure at the bottom of a barrel filled with liquid does not depend on the

A)acceleration of gravity.
B)liquid density.
C)height of the liquid.
D)area of the liquid surface.

Question 10

Heat conduction is least efficient in

A)metals.
B)nonmetallic solids.
C)water.
D)gases.

Question 11

The average pressure of the atmosphere at sea level corresponds to which one or more of the following?

A)101 Pa
B)101 kPa
C)98 kPa
D)15 lb/in²
E)Both B and D

Question 12

A barometer measures

A)atmospheric density.
B)atmospheric pressure.
C)water density.
D)water pressure.

Question 13

When heat is added to a body of matter, the resulting temperature increase does not depend upon

A)its mass.
B)its shape.
C)what kind of material it consists of.
D)whether it is in the solid, liquid, or gaseous state.

Question 14

Heat can be transferred through a solid by which one or more of the following?

A)conduction
B)convection
C)radiation
D)condensation
E)Both A and C

Question 15

Heat conduction is most efficient in

A)metals.
B)nonmetallic solids.
C)water.
D)gases.

Question 16

Heat can be transferred through a gas by which one or more of the following?

A)conduction
B)convection
C)radiation
D)condensation
E)Both A, B, and C

Question 17

Ice floats in water because

A)its density is less than that of water.
B)its specific heat is less than that of water.
C)it is a solid whereas water is a liquid.
D)it is colder than water.

Question 18

Which of the following formulas relating temperatures on the Celsius and Fahrenheit scales is correct?

A)T_c = (5/9)(T_F - 32 ^$\circ$ )
B)T_c = (5/9)(T_F + 32 ^$\circ$ )
C)T_c = (9/5)(T_F - 32 ^$\circ$ )
D)T_c = (9/5)(T_F + 32 ^$\circ$ )

Question 19

Of the substances below, the one with the highest specific heat is

A)water.
B)ice.
C)concrete.
D)gold.

Question 20

Heat can be transferred through a liquid by which one or more of the following?

A)conduction
B)convection
C)radiation
D)condensation
E)Both A, B, and C

Question 21

The physics underlying the operation of a refrigerator most closely resembles the physics underlying

A)a heat engine.
B)the melting of ice.
C)the freezing of water.
D)the evaporation of water.

Question 22

When a vapor condenses into a liquid,

A)its temperature decreases.
B)its temperature increases.
C)it absorbs heat.
D)it gives off heat.

Question 23

The temperature of a gas sample in a rigid container is raised.The pressure the gas exerts on the container walls increases because

A)the molecules are in contact with the walls for briefer intervals.
B)the molecular masses increase.
C)the molecules have higher average speeds and so strike the walls more often with greater momentum.
D)the molecules lose more kinetic energy each time they strike the wall.

Question 24

Suppose there were molecules that had no attraction whatsoever for one another.A collection of such molecules would form a

A)gas.
B)liquid.
C)amorphous solid.
D)crystalline solid.

Question 25

Of the following, a molecule is best described as

A)any very tiny particle.
B)the smallest particle found in nature.
C)the smallest particle of a substance that is representative of the substance.
D)the ultimate particle of which all matter is composed.

Question 26

The first law of thermodynamics is the same as the

A)second law of thermodynamics.
B)law of conservation of energy.
C)law of conservation of momentum.
D)first law of motion.

Question 27

In order to operate, a heat engine must have

A)either a hot or a cold reservoir.
B)both a hot and a cold reservoir.
C)a boiler.
D)a supply of fuel that can be burned, such as coal or oil.

Question 28

Which of the following is not true of molecular motion in a gas?

A)There is no order in the motion.
B)There is no uniformity of speed or direction.
C)There is a definite average speed at a given temperature.
D)There is a definite average direction of motion at a given temperature.

Question 29

The freezing point of a substance is always lower than its

A)melting point.
B)boiling point.
C)heat of fusion.
D)heat of vaporization.

Question 30

Molecular motion in a gas is the minimum possible at

A)0 ^$\circ$ F.
B)0 ^$\circ$ C.
C)0 K.
D)-273 K.

Question 31

Steam at 100 ^$\circ$ C is more dangerous than the same mass of water at 100 ^$\circ$ C because the steam

A)is less dense.
B)moves faster.
C)has a higher specific heat.
D)releases a great deal of heat when it condenses.

Question 32

When a liquid freezes to become a solid,

A)its temperature rises.
B)its temperature falls.
C)it absorbs heat.
D)it gives off heat.

Question 33

The maximum possible efficiency of a heat engine

A)is 100%.
B)depends on the intake temperature.
C)depends on the difference between the exhaust and intake temperatures.
D)depends on the ratio between the exhaust and intake temperatures.

Question 34

The work output of every heat engine

A)equals its heat intake.
B)equals the difference between its heat intake and heat exhaust.
C)depends only on its intake temperature.
D)depends only on its exhaust temperature.

Question 35

Molecules are, in general, farthest apart from one another in

A)gases.
B)liquids.
C)crystalline solids.
D)amorphous solids.

Question 36

The melting point of water is 0 ^$\circ$ C.Its freezing point is

A)slightly less than 0 ^$\circ$ C.
B)0 ^$\circ$ C.
C)slightly more than 0 ^$\circ$ C.
D)32 ^$\circ$ C.

Question 37

Sublimation refers to

A)the vaporization of a solid without first becoming a liquid.
B)the melting of a solid.
C)the vaporization of a liquid.
D)the condensation of a gas into a liquid.

Question 38

Which of the following formulas expresses the relationship between the pressure and absolute temperature of a gas sample whose volume is fixed?

A)
B)
C)
D)

Question 39

A sample of a gas is expanded to twice its original volume while its temperature is held constant.Relative to their original average energy, the new average energy of the molecules is

A)half as great.
B)the same.
C)twice as great.
D)four times as great.

Question 40

When a gas is forced into a smaller volume without a change in temperature, its pressure increases because its molecules

A)strike the container walls more often.
B)strike the container walls at higher speeds.
C)strike the container walls with greater force.
D)have more energy.

Question 41

A container holds 1 g of air at atmospheric pressure.When an additional gram of air is pumped into the container and there is no change in temperature, the new pressure is

A)0.5 atm.
B)1 atm.
C)2 atm.
D)4 atm.

Question 42

A 3-kg pine board is 20 cm wide, 2 cm thick, and 2 m long.The density of the board is

A)240 kg/m³.
B)267 kg/m³.
C)375 kg/m³.
D)469 kg/m³.

Question 43

The specific heat of water is 4.2 kJ/kg. ^$\circ$ C.How long will it take for a 2-kW heating element to raise the temperature of 30 kg of water from 20 ^$\circ$ C to 80 ^$\circ$ C?

A)6.3 min
B)15 min
C)63 min
D)84 min

Question 44

In an isolated system, entropy

A)cannot decrease.
B)must remain constant.
C)cannot increase.
D)may increase, decrease, or remain constant.

Question 45

In order to double the average energy of the molecules in a gas at 200 K, its temperature must be changed to

A)100 K.
B)400 K.
C)800 K.
D)1600 K.

Question 46

An absolute temperature of 100 K is the same as a Celsius temperature of

A)-173 ^$\circ$ C.
B)32 ^$\circ$ C.
C)212 ^$\circ$ C.
D)373 ^$\circ$ C.

Question 47

A 2-kg brick has the dimensions 7.5 cm * 15 cm * 30 cm.The pressure the brick exerts when standing on its smallest face is

A)0.0178 Pa.
B)0.0225 Pa.
C)178 Pa.
D)225 Pa.

Question 48

A refrigerator gives off

A)less heat than it absorbs from its contents.
B)the same amount of heat it absorbs from its contents.
C)more heat than it absorbs from its contents.
D)Any of these choices could be correct, depending on the circumstances.

Question 49

The specific heat of water is 4.2 kJ/kg. ^$\circ$ C.When 400 kJ of heat is added to 12 kg of water at 2 ^$\circ$ C, its final temperature is

A)5.9 ^$\circ$ C.
B)7.9 ^$\circ$ C.
C)11.7 ^$\circ$ C.
D)17.9 ^$\circ$ C.

Question 50

The density of air is 1.3 kg/m³.The air in a room 5 m long, 4 m wide, and 2.5 m high has a mass of

A)0.26 kg.
B)6.5 kg.
C)38 kg.
D)65 kg.

Question 51

The density of brass is 8 * 10³ kg/m³.The volume occupied by 320 g of brass is

A)0.038 cm³.
B)3.2 cm³.
C)38 cm³.
D)380 cm³.

Question 52

When 90 kJ is removed from a 2-kg copper bar, its temperature drops from 200 ^$\circ$ C to 85 ^$\circ$ C.The specific heat of iron is

A)0.16 kJ/kg. ^$\circ$ C.
B)0.19 kJ/kg. ^$\circ$ C.
C)0.23 kJ/kg. ^$\circ$ C.
D)0.39 kJ/kg. ^$\circ$ C.

Question 53

Oxygen boils at -183 ^$\circ$ C.This temperature is

A)-215 ^$\circ$ F.
B)-297 ^$\circ$ F.
C)-329 ^$\circ$ F.
D)-361 ^$\circ$ F.

Question 54

One liter of hydrogen gas at atmospheric pressure is allowed to expand to a volume of 3 liters with the temperature held constant.If the average speed of the hydrogen molecules was originally v, their new average speed is

A)v/9.
B)v/3.
C)v.
D)3 v.

Question 55

A temperature of 120 ^$\circ$ F is almost exactly

A)35 ^$\circ$ C.
B)49 ^$\circ$ C.
C)67 ^$\circ$ C.
D)88 ^$\circ$ C.

Question 56

The entropy of a system is a measure of its

A)temperature.
B)heat content.
C)density.
D)disorder.

Question 57

If the pressure on 10 m³ of air is increased from 200 kPa to 800 kPa, the new volume of air will be

A)1.25 m³.
B)1.67 m³.
C)2.5 m³.
D)40 m³.

Question 58

At which of the following Celsius temperatures will a Fahrenheit thermometer show the same reading in degrees?

A)-40 ^$\circ$ C
B)0 ^$\circ$ C
C)32 ^$\circ$ C
D)40 ^$\circ$ C

Question 59

A refrigerator

A)produces cold.
B)changes heat to cold.
C)causes heat to disappear.
D)removes heat from a region and carries it elsewhere.

Question 60

The specific heat of ice is 2.1 kJ/kg. ^$\circ$ C.When 20 kJ of heat is removed from 1.2 kg of ice originally at -5 ^$\circ$ C, its new temperature is

A)-18 ^$\circ$ C.
B)-23 ^$\circ$ C.
C)-26 ^$\circ$ C.
D)35 ^$\circ$ C.

Question 61

An ideal frictionless engine takes in 10 kJ of heat per second when it operates between 500 K and 400 K.The work that the engine does per second is

A)2 kJ.
B)2.5 kJ.
C)8 kJ.
D)10 kJ.

Question 62

If a heat engine that exhausts heat at 400 K is to have an efficiency of 33%, it must take in heat at a minimum of

A)133 K.
B)449 K.
C)532 K.
D)600 K.

Question 63

An ideal frictionless engine absorbs heat at 400 K and exhausts heat at 300 K.Its efficiency is

A)25%.
B)33%.
C)75%.
D)133%.

Question 64

Fifty kJ of heat is added to a 10-kg piece of lead at its melting point of 330 ^$\circ$ C and 2 kg of lead melts.The heat of fusion of lead is

A)2.5 kJ/kg.
B)3.3 kJ/kg.
C)5 kJ/kg.
D)25 kJ/kg.