Question

Plato classes The pH scale measures the acidity of a liquid as a function of its hydrogen ion (H+) concentration. How does the H+ concentration of a solution with a pH of 2 compare with that with a pH of 1?

Answer 1

Let H₁ be the concentration of a solution with a pH of 1, and H₂ be the concentration of a solution with a pH of 2, then:

`\begin{gathered} 1=-\log(H_1), \\ 2=-\log(H_2). \end{gathered}`

Then:

`\begin{gathered} H_1=10^(-1)=0.1, \\ H_2=10^(-2)=0.01. \end{gathered}`

Therefore:

`H_1=0.1H_2.`

Therefore the H concentration in a solution with a pH of 2 is 0.1 times of a solution with a pH of 1.

Answer: Second option.