Zinc metal reacts with hydrochloric acid to produce hydrogen gas. what best describes this reaction?
a. A single replacement reaction takes place because zinc is more reactive and hydrogen
b. A single replacement reaction takes place because zinc is more reactive than chlorine
c. A double replacement reaction takes place because zinc is less reactive than hydrogen
d. A double replacement reaction takes place because zinc is less reactive than chlorine

a. A single replacement reaction takes place because zinc is more reactive and hydrogen

In voltaic series  

Li-K-Ba-Ca-Na-Mg-Al-Mn- (H2O) -Zn-Cr-Fe-Cd-Co-Ni-Sn-Pb- (H) -Cu-Hg-Ag-Pt-Au  

The more to the left, the metal is more reactive (easily release electrons) and the stronger reducing agent  

The more to the right, the metal is less reactive (harder to release electrons) and the stronger oxidizing agent

So that the element located on the left can push the element on the right in the redox reaction

Reaction

Zn+2HCl ⇒ ZnCl₂ + H₂

If we look at this reaction, the elements that play a role are those that undergo a redox reaction

Oxidation : Zn⇒Zn²⁺ + 2e

Reduction : 2H⁺ + 2e ⇒H₂

So Zn (located on the left) can push H (the element on the right) in the redox reaction ⇒ Zn more reactive

A single replacement reaction is a chemical reaction in which one element replaces the other elements of a compound to produce new elements and compounds

A+BC⇒AC+B

So the above reaction involves the elements Zn and H which undergo a redox reaction and are included in a single replacement

- "the choice that is not an indicator of a chemical change is "state of matter changes". more common than not, chemical reactions produce energy in the form of light or heat. along with energy, they also produce a new substance called the product that could be in any state of matter (solid, gas, or liquid)."

c is the answer because when something is left after something evaporates that shows the chemical change.