Answer to Question #134434 in General Chemistry for Adina Rehan

Question

If the percent ionization of a 0.125 M solution of HNO2 is 6.50%, what is the pH of the solution?

Answer 1

percent ionization is the percentage ratio of the concentration of hydrogen ions to the concentration of the acid solution.

Nitric acid is a strong monobasic acid ,that dissociates fully in water.

$\%\; Ionization\; =\; [H+]/[HNO2]$ $Percent ionization =[H^+]/[HNO2]$ $\%$

Percent ionization = 6.50%

[HNO₂] = 0.125M

6.50% = [H⁺]/[0.125M]

the concentration of hydrogen ions can be obtained as;

[H⁺] = (6.50/100) * 0.125M

[H⁺] = 0.008125M

pH can be calculated as follows ;

$pH = -Log[H^+]$

$pH=-Log(0.008125)$

$pH =2.0917$

$\%$

$\%\; ionization\; =\; [H]/[HNO]\; *\; 100$