34 Limestone is a sedimentary rock consisting mostly of calcium carbonate (CaCO3). Which process is
most likely to cause a chemical change to limestone?
F Freezing water cracking limestone
G Flowing water eroding a limestone riverbed
H Acid rain forming puddles on limestone
J Coastal waves dissolving limestone sediments
35 A 500 mL quantity of vanilla ice cream has a mass of 400 grams. The manufacturer then bubbles air into
the ice cream so that its volume increases by 300 mL. What is the ice cream’s approximate final density?
F 0.30 g/cm 3
G 0.50 g/cm 3
H 0.80 g/cm 3
J 1.30 g/cm 3
36 Calcium ions play an important role in the function of neurons in the brain. Elements that are chemically
similar to calcium can interfere with the function of neurons. Which of the following is most likely to
imitate calcium’s role in the function of neurons?
37 The mass of a rusty bicycle is found to be slightly greater than the mass of the same bicycle before it rusted. The change in mass indicates that the rusting process —
A is a physical change
B involves an energy-to-matter conversion
C decreases the density of the metal
D involves metal bonding with other atoms
38 The diagram on the right shows water molecules and ions from an NaCl crystal. What is the most likely reason that each water molecule is arranged so that the oxygen part of the molecule faces a sodium ion?
F The oxygen in a water molecule contains a partial negative charge.
G Gravity rotates the oxygen atoms to face the more-massive sodium ions.
H Hydrogen atoms create repulsive forces with chloride ions.
J Oxygen atoms form covalent bonds with sodium ions.
39 Water acts as a solvent of ionic compounds because —
F water is liquid over a wide range of temperatures
G water molecules are polar
H water is found in three states of matter
J water takes the shape of its container
40 The table shows data from an investigation designed to find a liquid solution that is both an acid and a
strong electrolyte. Based on the data, a solution that is both an acid and a strong electrolyte is —
A Solution 1
B Solution 2
C Solution 3
D Solution 4
41 Which of these remains the same while water molecules go through the water cycle?
F The ratio of oxygen to hydrogen in the molecules
G The rate of vibration of the molecules
H The kinds of dissolved substances between the molecules
J The amount of energy the molecules can absorb
42 A bar of soap produced by this soap-making process normally sinks to the bottom of a container of
water. Which of these processes could cause the bar of soap to float in water?
A Making grooves in the surface of the thick paste
B Adding air bubbles to the thick paste
C Letting the thick paste sit for four days
D Chilling the mold filled with the thick paste
43 Which of the following is an example of a chemical change?
A Combustion of gasoline
B An apple being bitten
C An ice cube being swallowed
D Absorption of a water molecule
44 Aluminum metal and oxygen gas combine to produce aluminum oxide (Al2O3). Which of these is the
balanced equation for this reaction?
F Al + O2 ；;Al2O3
G 2Al + 2O2 ；;2Al2O3
H 2Al + 3O2 ；;5Al2O3
J 4Al + 3O2 ；;2Al2O3