Cн(KOH) =Cм(KOH)
Cм(KOH)=0,4моль/л; m(KOH)=0,4*56=22,4г-в 1 литре р-ра, а в 200мл - 22,4/5=4,48г.
m(H2O)=200-4,48=195,52г.
m( KOH)=4,48г
ОТВЕТ: m(H2O)=195,52г
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