Question

Buna , ma puteti ajuta? Calculeaza masa de solutie de acid clorhidric (HCl) 20% necesar reactiei cu 400g oxid de magneziu(MgO).
Mg-24; O-16; Cl-35,5; H-1.

Answer 1

2HCl+MgO-->MgCl2+H2O

M MgO=24+16=40 g/mol
n=m/M=400/40=10 moli MgO

2 moli HCl............1 mol MgO
x moli HCl.............10 moli MgO => x=20 moli HCl
M HCl=36,5 g/mol
m=n*M=730 g HCl (md)
c=100md/ms=>ms=100md/c=100*730/20=3650 g solutie HCl c=20%