Дано
W(KOH)=28%
p(KOH) =1.263g/mL
---------------------------
Cн-?
Сн = n/ Vppa ,Vppa = 1 L = 1000 mL
m(ppa KOH)= p(KOH) * Vppa = 1.263*100 = 1263 g
m(KOH) = 1263*28%/100%= 353.64 g
M(KOH) = 56 g/mol
n(KOH) = m(KOH) / M(KOH) = 353.64 / 56 = 6.315 mol
Cn = 6.315 /1000 = 0.006315 H
ответ 0.006315Н