Which value on the pH scale is neutral?

Which value on the pH scale is neutral?

• A. 7
• B. 0
• C. 14
• D. 1

Answer: (A)

Neutral on the pH scale means the solution is neither acidic nor basic. It happens when the hydrogen ion concentration equals the hydroxide ion concentration, which in pure water at room temperature is about 1×10^-7 M for each. The pH is the negative logarithm of the hydrogen ion concentration, so -log(1×10^-7) equals 7, the neutral point. Values below 7 are acidic, while values above 7 are basic, so 7 is the neutral value.

Neutral on the pH scale means the solution is neither acidic nor basic. It happens when the hydrogen ion concentration equals the hydroxide ion concentration, which in pure water at room temperature is about 1×10^-7 M for each. The pH is the negative logarithm of the hydrogen ion concentration, so -log(1×10^-7) equals 7, the neutral point. Values below 7 are acidic, while values above 7 are basic, so 7 is the neutral value.