Question 1

Why is the pH scale logarithmic?

Accepted Answer

Hydrogen ion concentrations in solutions vary over many orders of magnitude (from 1 M to 10^-14 M). The logarithmic scale compresses this enormous range into a convenient 0-14 scale for practical use.

Question 2

Can pH be negative or greater than 14?

Accepted Answer

Yes, technically. Very concentrated strong acids can have negative pH values, and very concentrated strong bases can exceed pH 14. However, the 0-14 range covers the vast majority of common solutions.

Question 3

What is the relationship between pH and pOH?

Accepted Answer

At 25C (standard temperature), pH + pOH always equals 14. This comes from the ion product of water (Kw = 10^-14). If you know one value, you can easily calculate the other.

Question 4

Why does pH matter in everyday life?

Accepted Answer

pH affects countless processes: your stomach needs low pH for digestion, your blood requires precise pH for survival, pool pH affects sanitizer effectiveness and swimmer comfort, and soil pH determines which plants can grow.

pH Calculator