Question

Calculati cantitatea de KOH care ar trebui sa neutralizeze 126 g solutie HNO3 de c=40%.
Determinati concentratia sarii rezultate din reactie.

Answer 1

KOH+HNO3->KNO3+H20

c=md*100/ms

md=c*ms/100=40*126/100=50,4gHNO3

MKOH=AK+AO+AH=39+16+1=56g

MHNO3=AH+AN+3*AO=1+14+3*16=63g

MKNO3=AK+AN+3*AO=39+14+3*16=101g

MH2O=2*AH+AO=2*1+16=18g

x/56=50,4/63 -> x=56*50,4/63=44,8 g KOH

y/101=50,4/63 -> y=101*50,4/63=80,8 g KNO3(md2)

z/18=50,4/63 -> z=18*50,4/63=14,4g H2O

ms=md+mapă 1->mapă1=ms-md=75,6g mapă=14,4+75,6=90

ms2=md2+mapă=80,8+90=170.8 g soluție KNO3

c=80,8*100/170,8=47,3%