C=md/ms*100⇒md=3,65g HCl
2M + 6HCl ⇒ 2MCl3 + 3H2
2Mg...................6*36,5g HCl
0,9g...................3,65g HCl
7,3M=197,1⇒M=27g
Metalul corespunzator ⇒ Al, M=27g/mol
n=m/M=0,9/27=0,0333 moli Al
n=m/M=3,65/36,5=0,1 moli HCl
HCl in exces..
2 moli Al...........................3*2g H2
0,0333 moli Al...................xg H2
x=6*0,333/2= Calculeaza !