1/
a, $Na_2O$, $M= 23.2+16= 62$
b, $ZnCl_2$, $M= 65+71= 136$
c, $Cu(OH)_2$, $M= 64+17.2= 98$
d, $Fe(NO_3)_3$, $M= 56+(14+16.3).3= 242$
e, $AlPO_4$, $M= 27+31+16.4= 122$
f, $CaSO4$, $M= 40+96= 136$
2/
$n_{CO_2}= \frac{11}{44}= 0,25 mol$
$V_{H_2}= \frac{9}{6}.22,4= 33,6l$
3/
$n_{O_2}= \frac{67,2}{22,4}= 3 mol$
Số phân tử oxi = $3.6.10^{23}= 18.10^{23}$
$m_{O_2}= 3.32= 96g$
Trong 3,2g oxi:
$n_{O_2}= \frac{3,2}{32}= 0,1 mol$
=> $n_{N_2}= 4n_{O_2}= 0,4 mol$
=> $m_{N_2}= 0.4.28= 11,2g$
4/ 5/ (hình)