Question

When a 0. 1 m aqueous solution of hydrocyanic acid, hcn, reaches equilibrium, the ph is measured to be 5. 20. using this information, calculate ka for hydrocyanic acid

Answer 1

When a 0. 1 m aqueous solution of hydrocyanic acid, HCN, reaches equilibrium, the ka for hydrocyanic acid is  3.969 x 10⁻¹⁰.

What is ka value?

It's the value of equilibrium constant for the dissociation of ions into a solution. The more the Ka value the more will be dissociation.

Ka = [H₃O⁺]² / [HCN] [H₃O⁺]

The pH is 5.20

-log [H₃O⁺] = 5.20

Putting antitlog both side.

The value will be 6.30 x 10⁻⁶

Ka = (6.30 x 10⁻⁶)²  / 0.1 - 6.30 x 10⁻⁶

0.1 - 6.30 x 10⁻⁶ = 0.1

Ka = 3.969 x 10⁻¹⁰

Thus, the Ka value for hydrocyanic acid is 3.969 x 10⁻¹⁰.

To learn more about ka value, refer to the link:

brainly.com/question/2796803

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