Se da:
m(Al)=90 g
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m(AlBr3)-?
v(AlBr3)-?
Rezolvare:
2Al+3Br2------>2AlBr3
1)Claculam niu (v) a Al: v(Al)=90:27=3,33 mol
2)Alcatuim raportul: 3,33 mol==x mol<=> x =3,33*2 =3,33 mol
2 mol==2 mol<=> x= 2
3)Calculam masa AlBr3: m(AlBr3)=3,33 mol*267 g/mol=889,11 g
Mr(AlBr3)=27+80*3=267 g/mol
Mr(Al)=27 g/mol
Raspuns:m(AlBr3)=889,11 g
v(AlBr3)=3,33 mol