Chapter 7:
Molecules in Motion
Practice Test
1.
Some liquids are more resistant to changing shape than others. What can you say about liquids, such as syrup, that pour slowly?
a.
There is a weaker attraction between the molecules of liquids that pour slowly compared to liquids that pour quickly.
b.
The molecules are probably far apart from one another.
c.
They have a high viscosity.
d.
They behave as solids.
Hint
2.
Why does a solid undergo thermal expansion when it is heated?
a.
The forces holding the particles together increase.
b.
The atoms compress.
c.
As the temperature of a solid increases, its atoms or molecules vibrate with greater speed and amplitude.
d.
This can happen only to solids that are malleable, such as clay.
Hint
3.
Over a period of several months, you notice that the ice cubes in your freezer get smaller and smaller and eventually disappear into a gas. Assuming the temperature in your freezer stays below freezing, what phase change have you observed?
a.
sublimation
b.
evaporation
c.
melting
d.
condensation
Hint
4.
On a hot day, you set an ice-cold glass of water outside on a table. You notice tiny beads of water appearing on the outside of the glass. What is the explanation?
a.
The glass is slowly melting.
b.
The water in the glass is undergoing sublimation.
c.
Water from the air is being cooled into a liquid onto a glass.
d.
Water is moving through the glass.
Hint
5.
Which of the following is a property of a solid?
a.
an object with a definite shape
b.
an object whose particles are held together by forces of attraction
c.
an object in which the ions, atoms, or molecules are in constant motion
d.
All of the above.
Hint
6.
How would you describe the kinetic-molecular theory?
a.
the explanation of thermal energy as the random movement of atoms or molecules
b.
the concept that an increase in thermal energy can vary depending the amount of mechanical work
c.
an experiment using falling cylinders to turn a paddle wheel inside an insulated container of water
d.
the idea that all matter is made up of atoms and molecules
Hint
7.
What is Boyle's law?
a.
At constant pressure, volume and temperature are directly proportional.
b.
At a constant pressure, volume and temperature are inversely proportional.
c.
At constant temperature, pressure and volume are directly proportional.
d.
At constant temperature, pressure and volume are inversely proportional.
Hint
8.
How is pressure described in terms of the kinetic theory of gases?
a.
Gases have no definite shape or volume.
b.
The particles of a gas exert a large force on one another.
c.
At constant temperature, pressure and volume are directly proportional.
d.
All of the above.
Hint
9.
What is the difference between evaporation and boiling?
a.
Evaporation is the process of a liquid changing to a gas and boiling is the point at which the pressure of the escaping vapor equals the air pressure.
b.
The molecules in a substance that evaporates are much closer together than the molecules of a substance that is boiled.
c.
There is no difference between them.
d.
Boiling refers to a liquid changing to a gas while evaporation refers to the solid changing to a gas.
Hint
10.
What is Charles's law?
a.
At constant temperature, pressure and volume are inversely proportional.
b.
At constant temperature, pressure and volume are directly proportional.
c.
At constant pressure, volume and temperature are directly proportional.
d.
At constant pressure, volume and temperature are inversely proportional.
Hint
11.
Most substances contract when they go from a liquid to a solid. Pure water (H
2
O) is an exception to this rule. When liquid water cools below 4°C, it actually expands. What implication does this property have?
a.
When water freezes, its mass increases.
b.
Many forms of aquatic life are able to survive when lakes and rivers freeze over.
c.
Icebergs grow from the bottom of the ocean floor towards the surface of the water.
d.
Lakes, rivers, and creeks freeze from the bottom to the top.
Hint
12.
Which of the following statements is false?
a.
Both liquids and solids contain atoms and molecules that are held together by forces of attraction.
b.
The liquid you see in thermometers expands at a constant rate over a temperature range of about -20[degree symbol]C to +40[degree symbol]C.
c.
The attractive forces holding together the atoms and molecules of a liquid are stronger than those holding together a solid.
d.
Both liquids and solids expand when they are heated.
Hint
13.
When you put an ice cube into water, what factor contributes to the temperature decrease of the water?
a.
The molecules in the water are closer together than they were before you added the ice cubes.
b.
The energy that melts the ice comes from the water.
c.
The attractive forces holding together the atoms and molecules of a liquid are stronger than those holding together a solid.
d.
All of the above are correct.
Hint
14.
What happens at the temperature known as absolute zero?
a.
Water changes from a liquid to ice.
b.
Molecules have only a tiny amount of energy.
c.
Molecules have zero energy.
d.
All of the above.
Hint
15.
What do scientists today consider to be a crystal?
a.
a solid that forms from the freezing of a pure liquid
b.
a transparent solid
c.
a solid made of millions of atoms connected by subatomic connections
d.
a solid whose atoms are arranged in a pattern that is repeated over and over again
Hint
