How many grams of hydroiodic acid are dissolved in 500. mL of a solution with a pH of 1.2?

1 Answer
Apr 6, 2018

Consider,

#HI(aq) rightleftharpoons H^(+)(aq) + I^(-)(aq)#

If #"pH" = 1.2#, then,

#[H^+] = 10^-1.2 = 0.0631"M"# at equilibrium.

#HI# is a strong acid, so generally #[H^+] = [HI] = 0.0631"M"#.

Hence,

#0.500"L" * 0.0631"M" * (127.9"g")/"mol" approx 4.03"g"#

of #HI# are dissolved in this very acidic solution.