Answer:
[H3O+] = 9.17x10-5
Explanation:
HClO + H2O -> H3O+ + ClO
Use the equation: Ka = [H3O+][ClO] / [HClO]
Initial concentration of HClO is 0.290M. Change in HClO is -x (we are losing reactants). So the equilibrium concentration will be 0.290-x.
Initial concentration of H3O+ and ClO is 0 because no products have been made yet. Change in both products will be +x (we are gaining reactants). So the equilibrium concentration will be +x.
Now, plug into the equation.
2.9x10-8 = (x)(x) / 0.290 - x
Simplify:
2.9x10-8 = x^2 / 0.290-x
Now because Ka is a very small number, it will not affect the the -x in 0.290, so we can ignore that.
2.9x10-8 = x^2 / 0.290
Now solve for x by multiplying 0.290 on both sides:
8.41x10-9 = x^2
Square root both sides to solve for x.
x = 9.17x10-5 = [H3O+]
