Răspuns:
Explicație:
HCl
1 + 35,5 = 35,5 g/mol
H2CO3
1 x 2 + 12 + 3 x 16 = 2 + 12 + 48 = 62 g/mol
H2SO4
1 x 2 + 32 + 4 x 16 = 2 + 32 + 64 = 98 g/mol
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M AlBr3 = 27 + 3 x 80 = 27 + 240 = 267 g/mol
267 g AlBr3.........................27 g Al
m............................................20 g Al
m = 20*267/27 = 197,8 g AlBr3