Answer:
Water, H2O, is a pure substance, a compound made of hydrogen and oxygen. Although water is the most abundant substance on earth, it is rarely found naturally in its pure form. Most of the time, pure water has to be created. Pure water is called distilled water or deionized water.
The correct response I believe is D. The reaction rate increases because the probability of collisions increases as there are more Zn atoms to react.
Answer:
The final balanced equation is :

Explanation:

Balancing in acidic medium:
First we will determine the oxidation and reduction reaction from the givne reaction :
Oxidation:

Balance the charge by adding 2 electrons on product side:
....[1]
Reduction :

Balance O by adding water on required side:

Now, balance H by adding
on the required side:

At last balance the charge by adding electrons on the side where positive charge is more:
..[2]
Adding [1] and [2]:

The final balanced equation is :
