Răspuns:
Explicație:
I.
a.---------moli
b. ---------masa-----
c. ---------100g
d.-----------atomi
II.
Ca(OH)2------------------CO2
2 O 2 O
Mg(NO3)2---------------------Ca(HCO3)2
6 O 6 O
CuCO3-------------------------NaNO3
3 O 3 O
Na2O----------------------------CuO
1 O 1 O
III.
Cu(NO3)2 r.a.= 1 : 2 : 6
IV.
Al2 (CO3)3
r.m.= 2 . 27 : 3 . 12 : 9 .16
=54 : 36 : 144 se simplif. cu 6
= 9 : 6 : 24 se simplif. cu 3
= 3 : 2 : 8
V
C9 H8 O4
M= 9.12 + 8 + 4.16=180--------> 180g/moli
180g C9H8 O4---------108 g C--------8 g H-------64 g O
100g-------------------------y-------------------z---------------m
y= 100.108 : 180=60% C
z=100.8 : 180= 4,44 % H
m= 100 . 64 : 180=35,56% O
VI.
MSi O2= 28 + 2.16=60-------> 60g/moli
60g SiO2----------32g O
yg-----------------------112 g O
y= 60 .112 : 32 =210 g SiO2
