Percent Ionization of Hydrocyanic Acid, HCN

14 Dec 2021

What is the percent ionization of a 0.0550 M solution of hydrocyanic acid, HCN?

How can we calculate the percent ionization of hydrocyanic acid, HCN, based on the given data?

The percent ionization of a 0.0550 M solution of hydrocyanic acid, HCN, is 0.0287%.

To calculate the percent ionization of a 0.0550 M solution of hydrocyanic acid, HCN, we can use the provided formula:

Percent ionization = ([H⁺]/[HCN]) x 100

First, we need to find the concentration of hydrogen ions using the Ka of HCN:

Ka = [H⁺][CN⁻] /[HCN]

6.17 x 10⁻¹⁰ = [H⁺][CN⁻]/0.0550

Assuming [H⁺] = [CN⁻] (since HCN is a weak acid), we can substitute [H⁺] for [CN⁻] in the equation:

6.17 x 10⁻¹⁰ = [H⁺]²/0.0550

[H⁺] = √(6.17 x 10⁻¹⁰ x 0.0550)

[H⁺] = 1.58 x 10⁻⁶ M

Now, we can plug this value back into the formula for percent ionization:

Percent ionization = (1.58 x 10⁻⁶/ 0.0550) x 100

Percent ionization = 0.0000287 × 100%

Percent ionization = 0.0287%

Therefore, the percent ionization of hydrocyanic acid, HCN, is 0.0287%.