Choose the correct answer

1			The scientist who discovered oxygen was
			A)	Joseph Priestley.
			B)	Johann Becher.
			C)	Fritz Haber.
			D)	Antoine Lavoisier.
2			According to the phlogiston hypothesis,
			A)	all substances that can be burned contain phlogiston.
			B)	as a substance burns, the phlogiston it contains is turned into ash or powder.
			C)	metals are considered to be solid forms of pure phlogiston.
			D)	phlogiston must be present in air before a substance can be burned.
3			The phlogiston hypothesis was overthrown as a result of the experiments conducted by
			A)	Georg Stahl.
			B)	Joseph Priestley.
			C)	Antoine Lavoisier.
			D)	Johann Becher.
4			When heated in the presence of air, tin turns into a white powder. The substance in the air that combines with the tin to form the white powder is
			A)	nitrogen.
			B)	hydrogen.
			C)	carbon dioxide.
			D)	oxygen.
5			In the preceding question, the tin has been
			A)	activated.
			B)	oxidized.
			C)	tempered.
			D)	alloyed.
6			The burning of coal, in which energy is liberated, is a(n)
			A)	exothermic reaction.
			B)	endothermic reaction.
			C)	catalytic reaction.
			D)	equilibrium reaction.
7			A compound is usually relatively stable if
			A)	its decomposition is weakly exothermic.
			B)	it liberates energy when decomposed.
			C)	a great deal of energy is needed to decompose the compound.
			D)	the PE of its electrons is high.
8			The rate of a chemical reaction can be increased by
			A)	lowering the temperature of the reaction.
			B)	reducing the concentration of the reactants.
			C)	increasing the surface area of a solid reactant.
			D)	lowering the activation energy.
9			Catalysts used by living organisms to regulate their chemical processes are called
			A)	hormones.
			B)	steroids.
			C)	enzymes.
			D)	lipids.
10			A disadvantage in using fuel cells to power automobiles is
			A)	their relatively short life span.
			B)	a high weight to electrical power ratio.
			C)	the release of large amounts of CO2 into the atmosphere.
			D)	the safe storage of hydrogen fuel needed for a moderately long trip.

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Refer to the above drawing to answer questions 11–13.

11			The drawing represents
			A)	combustion of molten NaCl.
			B)	transmutation of NaCl
			C)	catalytic dissociation of NaCl.
			D)	electrolysis of molten NaCl.
12			The current in the molten NaCl consists of
			A)	moving Na and Cl atoms.
			B)	moving Na+ and Cl− ions.
			C)	moving Cl− ions only.
			D)	moving electrons.
13			The process illustrated by the drawing is an example of
			A)	an oxidation reaction only.
			B)	a reduction reaction only.
			C)	both oxidation and reduction reactions.
			D)	an acid-base neutralization reaction.

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Refer to the above drawing to answer questions 14–15.

14			The nitrate ions (NO3−) remain in solution because
			A)	nitrate ions are more soluble than silver ions.
			B)	silver atoms lose electrons at the anode more readily than nitrate ions.
			C)	the mass of a nitrate ion is less than that of a silver ion.
			D)	silver ions have a greater tendency to react with the metals than do nitrate ions.
15			Silver atoms are reduced at the
			A)	spoon.
			B)	anode.
			C)	battery.
			D)	cathode.