Question

K-KOH-KHSO4-K2SO4-BaSO4

Answer 1

2K + 2H2O = 2KOH + H2

KOH + H2SO4(конц, хол) = KHSO4 + H2O

KHSO4 + KOH(конц.) = K2SO4 + H2O

K2SO4 + Ba(OH)2 = BaSO4 + 2KOH