What happens to the concentration of hydrogen ions in a solution as you move from 7 down the ph scale toward 0?

Hydrogen ion (H⁺) increases.

Explanation:

A solution can be acidic, basic or may be neutral. It know the exact nature of the solution, the pH is a scale which is used. The pH scale ranges from 0 to 14. The pH 7 is neutral and the reading of a solution on pH scale 6.9 to 0.0 is acidic and the reading on pH scale 7.1 to 14.0 is basic. In an acidic solution the hydrogen ion  (H⁺) concentration is more compared to a basic solution. Thus, the concentration of hydrogen ions  (H⁺) in a solution increases when we move from 7 to 0 on the pH scale. The solution with 0 PH is the strongest acid and 6.9 is weak acid.

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