Răspuns:
M,HBr= 81g/mol
-calculez masa de magneziu pur
p=m,px100/m,i---> m,p=1000x96/100g=960g
2x81g......24g
2HBr + Mg ----> MgBr2 + H2
x................960g
x=mHBr=6480g aceasta masa de acid se afla dizolvata in solutia data
c= mdx100/ms----> ms=6480x100/20g=32400g= 32,4kg
Explicație: