Question

What is the concentration of H3O+ in a solution with a pH of 4.73?

Select one:
A. 1.9 x 10-6 M
B. 5.3 x 10-10 M
C. 5.3 x 10-9 M
D. 1.9 x 10-5 M

Answer 1

Explanation:

Calculating the Hydronium Ion Concentration from pH [H3O+] = 10-pH or [H3O+] = antilog (- pH) Example: What is the hydronium ion concentration in a solution that has a pH of 8.34? On a calculator, calculate 10-8.34, or "inverse" log ( - 8.34).

Answer 2

Given: A solution has a pH of 4.73.

To find: We have to find the concentration of $H_3O^+$ ion.

Solution:

To determine the concentration of $H_3O^+$ ion we have to use the below formula-

pH=-log$[H_3O^+]$

Here the given value of pH of the solution is 4.73.

Putting the value of pH in the above formula we get-

4.73=-log$[H_3O^+]$

Let $[H_3O^+]$ be equal to x.

$4.73 = - log(x) \\ - 4.73 = log(x) \\ {10}^{ - 4.73} = x \\ x = 1.9 \times {10}^{ - 5}$

The value of x is $1.9×10^{-5}$.

Thus, the concentration of $H_3O^+$ is $1.9×10^{-5}$M.

The correct option is D.