Question

pure water has a ph of 7. pure water .........
options:

• is an acid
• could be either an acid or a base
• is a neutral substance
• is a base

Explanation:

The question is about the pH of pure water. In chemistry (a subfield of Natural Science), a pH of 7 is defined as neutral. Pure water has a pH of 7, so it is a neutral substance. The other options are incorrect: acids have pH < 7, bases have pH > 7, and pure water is not either acid or base.

Answer:

The third option (the one with "is a neutral substance")