Which of these statements is true?
a. If a compound is oxidized, it is gaining electrons.
b. If a base is neutralized, it is gaining protons.
c. Elements that are metals cannot be oxidized.
d. If hydrogen gas is generated in a reaction, it must be an acid–base reaction.

An aqueous solution contains 1.2 mM of total ions. (a) If the solution is NaCl(aq), what is the concentration of chloride ion?

You are presented with a white solid and told that due to careless labeling it is not clear if the substance is barium chloride, lead chloride, or zinc chloride. When you transfer the solid to a beaker and add water, the solid dissolves to give a clear solution. Next an Na2SO41aq2 solution is added and a white precipitate forms. What is the identity of the unknown white solid?

Which of the following ions will always be a spectator ion in a precipitation reaction? (a) Cl- (b) NO3- (c) NH4+ (d) S2- (e) SO42-

The concept of chemical equilibrium is very important. Which one of the following statements is the most correct way to think about equilibrium? (a) If a system is at equilibrium, nothing is happening. (b) If a system is at equilibrium, the rate of the forward reaction is equal to the rate of the back reaction. (c) If a system is at equilibrium, the product concentration is changing over time.

What kind of reaction is this? N2(g)+3H2(g)⟶2NH3(g)

a. an acid–base reaction

b. a metathesis reaction

c. a redox reaction

d. a precipitation reaction

An aqueous solution contains 1.2 mM of total ions. (b) If the solution is FeCl3(aq), what is the concentration of chloride ion?