Chemistry: The Science of Matter
Practice Test
1.
When water reacts with baking powder, _______ gas is produced.
a.
ammonia
b.
carbon dioxide
c.
nitrogen
d.
helium
2.
The density of cork is _______________.
a.
1.00 g/mL
b.
11.34 1.00 g/mL
c.
less than 1.00 g/mL
d.
more than 1.00 g/mL
3.
A volatile substance is one that ____________________ at room temperature.
a.
condenses
b.
decomposes readily
c.
changes to a gas easily
d.
freezes readily
4.
An exothermic reaction is one that _______________.
a.
causes a color change
b.
gives off energy
c.
absorbs energy
d.
produces a solid
5.
An object has a mass of 20.0 g and a volume of 10.0 mL. What is its density?
a.
20.0 g
b.
0.500 g/mL
c.
10.0 mL
d.
2.00 g/mL
6.
When water decomposes into hydrogen and oxygen, the mass _____________.
a.
decreases if the temperature exceeds 100oC.
b.
decreases
c.
increases
d.
remains constant
7.
Photosynthesis is _______________.
a.
endothermic
b.
a physical change
c.
a substance
d.
exothermic
8.
Crushing a substance ____________.
a.
decreases its melting point
b.
is a physical change
c.
increases its density
d.
is a chemical change
9.
How can the law of conservation of mass apply to a burning log, if all that remains of it is ash?
a.
The masses of the gases and water vapor released into the air by the combustion reaction plus the mass of ash equal the mass of the log before burning.
b.
The law of conservation of mass applies to changes of state but not to chemical reactions.
c.
The law of conservation of mass applies to substitution and displacement reactions, but not to combustion reactions.
d.
The ash has the same mass as the log, although a large percentage of it blows away.
10.
The capacity to do work is called ________.
a.
density
b.
volume
c.
mass
d.
energy
