Question

what is the pH of a 0.050 M concentration of the strong acid HI?

1.3
2.2
3.1
4.5

Answer 1

Correct Answer: 1.3

The pH of a solution is defined as the negative log of its hydrogen ion concentration. 

The concentration of HI is 0.050 M. Since one molecule of H has one atom, the concentration of hydrogen ions in 0.050M HI will be 0.050 moles.

So,

$pH=-log[ H^{+}] \\ \\ pH=-log(0.050) \\ \\ pH=1.3$

Therefore, the pH of 0.050M solution of HI will be 1.3.