Chapter 18, Problem 76A

Solution A has a pH of 2.0. Solution B has a pH of 5.0 Which solution is more acidic? Based on the $\text{H}+$ ion concentrations in the two solutions, how many times more acidic?

Interpretation Introduction

Interpretation:

The solution which is more acidic is to be determined using $pH$ values.

Concept introduction:

Acids have $pH$ in range $1-7$. Lesser the $pH$ value, more acidic is the solution.

$pH=-\log \left[H^{+}\right]$

Answer to Problem 76A

Solution A is more acidic. It is ${10}^3$ times more acidic than B.

Explanation of Solution

Solution A is more acidic because its $pH$ value is less than B.

$pH=2$ of solution A implies hydrogen ion concentration is ${10}^{-2}M$

$pH=5$ of solution B implies hydrogen ion concentration is ${10}^{-5}M$

Therefore, solution A is ${10}^3$ times more acidic than B.

Conclusion

Thus, solution A is more acidic. It is ${10}^3$ times more acidic than B.