Question

What is the $\left[H^{+}\right]$ of 0.1 M acetic acid $(K_a=1.8\times {10}^{-5})$?

• A. $1.34\times {10}^{-4}$
• B. $1.34\times {10}^{-2}$
• C. $1.34\times {10}^{-3}$
• D. $1.34\times {10}^{-6}$

Answer 1

The correct option is C $1.34\times {10}^{-3}$

$H^{+}$ = $\sqrt{K_a\times C}$

$H^{+}$ = $\sqrt{1.8\times {10}^{-5}\times 0.1}$

$H^{+}$ = $1.34\times {10}^{-3}$