Question 1

Why does a lake freeze from the top down?

Accepted Answer

A)  As cold water cools towards freezing it gets less dense. 
B)  The cold air is at the top of the lake. 
C)  Cold water sinks, warm water rises. 
D)  Warm water sinks, cold water rises. 
E)  none of the above 
A)  As cold water cools towards freezing it gets less dense. 
B)  The cold air is at the top of the lake. 
C)  Cold water sinks, warm water rises. 
D)  Warm water sinks, cold water rises. 
E)  none of the above

Question 2

From the diagram above describing the phase of xenon relative to temperature and pressure which is more dense: liquid xenon or solid xenon?

Accepted Answer

A)  solid 
B)  liquid 
C)  The density of xenon is the same in both the solid and liquid phase. 
D)  Density information can not be determined from the diagram. 
A)  solid 
B)  liquid 
C)  The density of xenon is the same in both the solid and liquid phase. 
D)  Density information can not be determined from the diagram.

Question 3

How are pressure and the boiling point of a compound related?

Accepted Answer

A)  As the pressure decreases the boiling point decreases. 
B)  As the boiling point increases the pressure decreases. 
C)  As the pressure decreases the boiling point increases. 
D)  As the boiling point decreases the pressure increases. 
E)  none of the above 
A)  As the pressure decreases the boiling point decreases. 
B)  As the boiling point increases the pressure decreases. 
C)  As the pressure decreases the boiling point increases. 
D)  As the boiling point decreases the pressure increases. 
E)  none of the above

Question 4

Heat is absorbed by a substance when that substance ________.

Accepted Answer

A)  freezes 
B)  evaporates 
C)  condenses 
D)  cools 
E)  A and C 
A)  freezes 
B)  evaporates 
C)  condenses 
D)  cools 
E)  A and C

Question 5

Water has a high specific heat because of its ________.

Accepted Answer

A)  transparency 
B)  density 
C)  polarity 
D)  phase 
A)  transparency 
B)  density 
C)  polarity 
D)  phase

Question 6

A walnut stuck to a pin is burned beneath a can containing 100.0 grams of water at 21°C. After the walnut has completely burned, the water's final temperature is a warmer 28°C. How much heat energy arose from the burning walnut?

Accepted Answer

A)  3,000 joules 
B)  9,000 joules 
C)  5,000 joules 
D)  2,000 joules 
A)  3,000 joules 
B)  9,000 joules 
C)  5,000 joules 
D)  2,000 joules

Question 7

An adhesive force is best described as ________.

Accepted Answer

A)  attraction between two liquid molecules 
B)  attraction between a liquid molecule and a solute 
C)  the force that allows for molecular adhesion 
D)  the force that holds together the nucleus 
E)  attraction between two different molecules 
A)  attraction between two liquid molecules 
B)  attraction between a liquid molecule and a solute 
C)  the force that allows for molecular adhesion 
D)  the force that holds together the nucleus 
E)  attraction between two different molecules

Question 8

The specific heat of a substance is the ________.

Accepted Answer

A)  amount of heat required to change the temperature of a given mass 
B)  amount of heat energy that is stored in chemical bonds 
C)  amount of potential energy in a material that is released when a substance undergoes combustion and gives off heat 
D)  temperature at which a compound starts to melt 
E)  temperature at which a given mass's heat increases 
A)  amount of heat required to change the temperature of a given mass 
B)  amount of heat energy that is stored in chemical bonds 
C)  amount of potential energy in a material that is released when a substance undergoes combustion and gives off heat 
D)  temperature at which a compound starts to melt 
E)  temperature at which a given mass's heat increases

Question 9

How does a solute such as salt or sugar affect the melting and freezing of water?

Accepted Answer

A)  Solutes slow the rate of ice formation. 
B)  Solutes increase the rate of ice formation. 
C)  Solutes slow the rate of liquid water release from ice. 
D)  Solutes increase the rate of liquid water release from ice. 
E)  none of the above 
A)  Solutes slow the rate of ice formation. 
B)  Solutes increase the rate of ice formation. 
C)  Solutes slow the rate of liquid water release from ice. 
D)  Solutes increase the rate of liquid water release from ice. 
E)  none of the above

Question 10

Why does adding heat to ice-water disfavor the rate of ice formation?

Accepted Answer

A)  Heat increases the vibration of the water molecules, which breaks the hydrogen bonds. 
B)  When heat is added, the water molecules are moving too fast to form hydrogen bonds, which gives it the structure that we call ice. 
C)  Adding heat favors the rate of melting, as more hydrogen bonds are broken than formed by the ice in the ice-water. 
D)  all the above 
A)  Heat increases the vibration of the water molecules, which breaks the hydrogen bonds. 
B)  When heat is added, the water molecules are moving too fast to form hydrogen bonds, which gives it the structure that we call ice. 
C)  Adding heat favors the rate of melting, as more hydrogen bonds are broken than formed by the ice in the ice-water. 
D)  all the above

Question 11

Why are polar oceans most fertile in the autumn?

Accepted Answer

A)  The warm summer temperatures allowed for the growth of many microorganisms in the water. 
B)  As the oxygen rich surface waters cool in the autumn, they sink to the bottom, displacing the layer of decomposing organic matter, forcing it to rise, adding nutrients to the surface of the polar oceans. 
C)  The salinity of the ocean is at a low point at that time of year. 
D)  Ocean currents tend to reverse during the autumn, bringing nutrient rich waters up from the equatorial regions. 
A)  The warm summer temperatures allowed for the growth of many microorganisms in the water. 
B)  As the oxygen rich surface waters cool in the autumn, they sink to the bottom, displacing the layer of decomposing organic matter, forcing it to rise, adding nutrients to the surface of the polar oceans. 
C)  The salinity of the ocean is at a low point at that time of year. 
D)  Ocean currents tend to reverse during the autumn, bringing nutrient rich waters up from the equatorial regions.

Question 12

Why does ice form at the surface of a body of fresh water instead of at the bottom?

Accepted Answer

A)  Initial freezing requires the presence of air in order to form the ice lattice, thus the surface water will become solid first. 
B)  Intermolecular forces are greater at the surface allowing the surface molecules to form the solid phase more quickly. 
C)  Water "near" the freezing point of 0°C is less dense than warmer water, and the colder water will "float" on the warmer water. This allows ice to form at the surface. 
D)  All of the above are true. 
A)  Initial freezing requires the presence of air in order to form the ice lattice, thus the surface water will become solid first. 
B)  Intermolecular forces are greater at the surface allowing the surface molecules to form the solid phase more quickly. 
C)  Water "near" the freezing point of 0°C is less dense than warmer water, and the colder water will "float" on the warmer water. This allows ice to form at the surface. 
D)  All of the above are true.

Question 13

Your inventor friend proposes a design of cookware that will allow boiling to take place at a temperature less than 100°C so that food can be cooked with less energy. Comment on this idea.

Accepted Answer

A)  This idea would not be very profitable because it is the high temperature and the resulting thermal energy given to the food that is responsible for cooking-if the water boils at a low temperature insufficient energy is given to cook the food. 
B)  This idea has already been invented and is called a crock pot, or a slow cooker. 
C)  This is impossible because water only boils at 100°C, unless it is in a vacuum, and it is not possible to create a vacuum outside of the lab. 
D)  It is a great way to cook food and save energy while preventing vitamins and nutrients from being destroyed in high temperatures. 
A)  This idea would not be very profitable because it is the high temperature and the resulting thermal energy given to the food that is responsible for cooking-if the water boils at a low temperature insufficient energy is given to cook the food. 
B)  This idea has already been invented and is called a crock pot, or a slow cooker. 
C)  This is impossible because water only boils at 100°C, unless it is in a vacuum, and it is not possible to create a vacuum outside of the lab. 
D)  It is a great way to cook food and save energy while preventing vitamins and nutrients from being destroyed in high temperatures.

Question 14

What happens to a soda can left in the freezer? Why?

Accepted Answer

A)  The sugar and syrup, which separate from the water, settle to the bottom of the can and become solid. 
B)  The soda inside the can freezes collapsing the can as the solid forms. 
C)  The soda can puffs out and sometimes the lid pops open because water expands when it freezes. 
D)  Although the soda inside the can get s very cold, it will not completely freeze because of the high sugar concentration. 
A)  The sugar and syrup, which separate from the water, settle to the bottom of the can and become solid. 
B)  The soda inside the can freezes collapsing the can as the solid forms. 
C)  The soda can puffs out and sometimes the lid pops open because water expands when it freezes. 
D)  Although the soda inside the can get s very cold, it will not completely freeze because of the high sugar concentration.

Question 15

Suppose 4 g of water at 100°C is spread over a large surface so that 1 g evaporates rapidly. If evaporation of the 1 gram takes 2,259 joules from the remaining 3 g of water and no other heat transfer takes place, what are the temperature and phase of the remaining 3 g once the 1 gram is completely evaporated?

Accepted Answer

A)  The remaining 3 g will turn to 10°C , liquid. 
B)  The remaining 3 g will turn to 20°C liquid. 
C)  The remaining 3 g will turn to -10°C ice. 
D)  The remaining 3 g will turn to 0°C ice. 
A)  The remaining 3 g will turn to 10°C , liquid. 
B)  The remaining 3 g will turn to 20°C liquid. 
C)  The remaining 3 g will turn to -10°C ice. 
D)  The remaining 3 g will turn to 0°C ice.

Question 16

If the heat of melting of a sample is 135 J/g, how much heat would be required to melt 5.00 grams of material?

Accepted Answer

A)  675 J 
B)  27 J 
C)  67 J 
D)  270 J 
E)  none of the above 
A)  675 J 
B)  27 J 
C)  67 J 
D)  270 J 
E)  none of the above

Question 17

To impart a hickory flavor to a roasted turkey, a cook places a pot of water containing hickory chips in an oven with the turkey. Why does the turkey take longer than expected to cook?

Accepted Answer

A)  Much of the heat from the oven is consumed in changing the phase of the water. 
B)  Because the turkey is being steamed instead of being baked. 
C)  To get a hickory flavor, you need to roast the turkey for a long time at a low temperature. 
D)  The wood of the hickory chips does not conduct heat very well. 
A)  Much of the heat from the oven is consumed in changing the phase of the water. 
B)  Because the turkey is being steamed instead of being baked. 
C)  To get a hickory flavor, you need to roast the turkey for a long time at a low temperature. 
D)  The wood of the hickory chips does not conduct heat very well.

Question 18

How much heat is required to raise the temperature of 100,000 grams of iron by 30°C?

Accepted Answer

A)  +1,000,000 joules 
B)  +343,000 joules 
C)  +1,353,000 joules 
D)  +7,390,000 joules 
A)  +1,000,000 joules 
B)  +343,000 joules 
C)  +1,353,000 joules 
D)  +7,390,000 joules

Question 19

Which of the following statements best describes the usual properties of most compounds besides water?

Accepted Answer

A)  The density of a material increases when it solidifies. 
B)  The volume of a material increases when it solidifies. 
C)  The mass of a material increases when it solidifies. 
D)  The molecules become more closely packed when they liquify. 
E)  none of the above 
A)  The density of a material increases when it solidifies. 
B)  The volume of a material increases when it solidifies. 
C)  The mass of a material increases when it solidifies. 
D)  The molecules become more closely packed when they liquify. 
E)  none of the above

Question 20

A gold ring cannot sit on the surface of water, but a thin gold wire loop of the same diameter can. Why?

Accepted Answer

A)  The gold ring applies a much greater pressure against the surface of the water so that it is able to push through the surface tension. 
B)  The surface area of contact is the same, but the weight of the gold ring is much greater. 
C)  The thin gold wire is far less dense than the gold ring, which allows it to float. 
D)  Both A and B are true. 
A)  The gold ring applies a much greater pressure against the surface of the water so that it is able to push through the surface tension. 
B)  The surface area of contact is the same, but the weight of the gold ring is much greater. 
C)  The thin gold wire is far less dense than the gold ring, which allows it to float. 
D)  Both A and B are true.

Why does a lake freeze from the top down?

From the diagram above describing the phase of xenon relative to temperature and pressure which is more dense: liquid xenon or solid xenon?

How are pressure and the boiling point of a compound related?

Heat is absorbed by a substance when that substance ________.

Water has a high specific heat because of its ________.

A walnut stuck to a pin is burned beneath a can containing 100.0 grams of water at 21°C. After the walnut has completely burned, the water's final temperature is a warmer 28°C. How much heat energy arose from the burning walnut?

An adhesive force is best described as ________.

The specific heat of a substance is the ________.

How does a solute such as salt or sugar affect the melting and freezing of water?

Why does adding heat to ice-water disfavor the rate of ice formation?

Why are polar oceans most fertile in the autumn?

Why does ice form at the surface of a body of fresh water instead of at the bottom?

Your inventor friend proposes a design of cookware that will allow boiling to take place at a temperature less than 100°C so that food can be cooked with less energy. Comment on this idea.

What happens to a soda can left in the freezer? Why?

If the heat of melting of a sample is 135 J/g, how much heat would be required to melt 5.00 grams of material?

To impart a hickory flavor to a roasted turkey, a cook places a pot of water containing hickory chips in an oven with the turkey. Why does the turkey take longer than expected to cook?

How much heat is required to raise the temperature of 100,000 grams of iron by 30°C?

Which of the following statements best describes the usual properties of most compounds besides water?

A gold ring cannot sit on the surface of water, but a thin gold wire loop of the same diameter can. Why?

About Science

Particles of Matter

Elements of Chemistry

Subatomic Particles

The Atomic Nucleus

How Atoms Bond

How Molecules Mix

How Chemicals React

Acids and Bases in Our Environment

Oxidations and Reductions Charge the World

Organic Compounds

Nutrients of Life

Medicinal Chemistry

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Exam 8: How Water Behaves

Why does a lake freeze from the top down?

From the diagram above describing the phase of xenon relative to temperature and pressure which is more dense: liquid xenon or solid xenon?

How are pressure and the boiling point of a compound related?

Heat is absorbed by a substance when that substance ________.

Water has a high specific heat because of its ________.

A walnut stuck to a pin is burned beneath a can containing 100.0 grams of water at 21°C. After the walnut has completely burned, the water's final temperature is a warmer 28°C. How much heat energy arose from the burning walnut?

An adhesive force is best described as ________.

The specific heat of a substance is the ________.

How does a solute such as salt or sugar affect the melting and freezing of water?

Why does adding heat to ice-water disfavor the rate of ice formation?

Why are polar oceans most fertile in the autumn?

Why does ice form at the surface of a body of fresh water instead of at the bottom?

Your inventor friend proposes a design of cookware that will allow boiling to take place at a temperature less than 100°C so that food can be cooked with less energy. Comment on this idea.

What happens to a soda can left in the freezer? Why?

If the heat of melting of a sample is 135 J/g, how much heat would be required to melt 5.00 grams of material?

To impart a hickory flavor to a roasted turkey, a cook places a pot of water containing hickory chips in an oven with the turkey. Why does the turkey take longer than expected to cook?

How much heat is required to raise the temperature of 100,000 grams of iron by 30°C?

Which of the following statements best describes the usual properties of most compounds besides water?

A gold ring cannot sit on the surface of water, but a thin gold wire loop of the same diameter can. Why?

About Science

Particles of Matter

Elements of Chemistry

Subatomic Particles

The Atomic Nucleus

How Atoms Bond

How Molecules Mix

How Chemicals React

Acids and Bases in Our Environment

Oxidations and Reductions Charge the World

Organic Compounds

Nutrients of Life

Medicinal Chemistry

Optimizing Food Production

Protection Water and Air Resources

Capturing Energy

Filters