Plz help. Strong acid

Question

Part A

For the strong acid solution 0.0626 M HBr, determine [H3O+] and [OH-].

Part B

For the strong acid solution 1.7×10⁻³ M HNO3, determine [H3O+] and [OH-]

Answer 1

0.0626 M HBr ==> 0.0626 M H+ + 0.0626 M Br-

[H3O⁺] = [H⁺] = 0.0626 M

[OH-] = 1x10^-14 / 0.0626 = 1.60x10^-13 M

1.7x10^-3 M HNO3 ==> 1.7x10^-3 M H⁺ + 1.7x10^-3 M NO3^-

[H3O⁺] = [H⁺] = 1.7x10^-3 M

[OH-] = 1x10^-14 / 1.7x10^-3 = 5.9x10^-12 M