repede pls am nevoie urgent

Răspuns:
100g Al.............70g Al pur
9g Al..............xgAl pur
x=9x70/100=3,6gAl pur
MAl=27g/mol
MAl(NO3)3=27+3x14+9x16=213g/mol
2x27....................2x213g
2Al + 6HNO3 → 2Al(NO3)3 + 3H2↑
3,6g.........................xg
x=3,6x2x213/2x27=calculeaza
Explicație: