Question

this passage describes a chemical reaction. read the passage. then, follow the instructions below.

when the statue of liberty in new york city was built in the late 1800s, it was reddish-brown. today, a green layer, called a patina, covers the statues surface. this layer formed over time as copper in the statue combined with oxygen and other gases in the air to form the patina.

complete the sentence.

in this chemical reaction, oxygen is a ______.

reactant

product

Explanation:

In a chemical reaction, reactants are the substances that undergo the reaction to form products. The passage states that copper combined with oxygen and other gases to form the patina. So oxygen is a reactant (since it's a substance that reacts, not a substance formed from the reaction).

Answer:

reactant