Answer:
.00402 %
Step-by-step explanation:
hydrocyanic acid (HCN) is a weak acid with a Ka of 6.17*10^-10 so you need to do a RICE table
initial concentration of HCN is .381 and initial H+ and CN- concentration is 0.
that means the equillibrium concentration of HCN will be (.381-x) and H+ and CN- will be x
put that into the formula for Ka, so it'll be Ka = x^2/(.381-x) and then use quadratic equation to solve. You'll end up getting x = 1.5 * 10^-5.
Then to find percent ionization you solve (concentration of formed ions / initial HCN)
Which will be (1.5 * 10^-5 / .381) * 100 = .00402 % making it a very weak acid <3