Chemistry Test Chemical Reactions 3

Question 1

What does it mean for a chemical reaction to be exothermic?

Accepted Answer

It releases heat into the surroundings

Answer

Exothermic reactions release energy as heat, making the surroundings feel warmer.

Question 2

In a neutralization reaction, an acid reacts with a base to produce:

Accepted Answer

A salt and water

Answer

Neutralization reactions produce a salt and water when an acid and base combine.

Question 3

Which factor does NOT affect the rate of a chemical reaction?

Accepted Answer

Color of the reaction vessel

Answer

The color of the reaction vessel has no effect on reaction rate; concentration, surface area, and catalysts all influence how fast reactions proceed.

Question 4

What is a precipitate in a double displacement reaction?

Accepted Answer

An insoluble solid that forms in solution

Answer

A precipitate is an insoluble solid product that forms when two solutions are mixed in a double displacement reaction.

Question 5

In the combustion reaction CH₄ + 2O₂ → CO₂ + 2H₂O, what is oxidized?

Accepted Answer

Carbon in methane

Answer

Carbon in methane is oxidized because it loses electrons (its oxidation state increases from -4 to +4).

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