Question

Un volum de solutie de KOH egal cu 100 cm cubi de concentratie 26 la suta si densitatea de 1.24 g pe cm cub reactioneaza cu o solutie de HCl de concentratie 10 la suta. Calculeaza masa de solutie de HCl necasara neutralizarii.

Answer 1

KOH+HCl=Kcl+H2O
M KOH=56
M HCl=36,5
densitate=m/V
m=densitate * V
m=1,24g/cm3 * 100 cm3
m=124 g solutie

c=md/ms*100
md=c*ms/100
md=26*124/100
md=32,24 g KOH

x=36,5*32,24/56
x=1176,76 g HCl pur

c=md/ms*100
ms=md*100/c
ms=1176,76*100/10
ms=11767,6 g solutie HCl

Answer 2

ro = ms/V
ms = 100*1,24 = 124 g KOH
c = md/ms * 100
md = 26*124/100 = 32,24 g KOH
KOH + HCl = KCl + H2O
M KOH = 39+16+1 = 56
M HCl = 1+35,5 = 36,5
56 g KOH..........36,5 g acid
32,24 g KOH...............x
x = 21,013 g HCl
c = md/ms*100
ms = 21,013/10*100 = 210,13 g soluție