Răspuns:
a) MCO2=12+2×16=44g/mol
n=112/44=2,54 moli
b) MH2O =2×1+16=18f/mol
m=18×5=90g
c)1mol...........6,022×10²³ molecule O2
xmoli............12,044×10²⁴ molecule O2
x=12,044×10²⁴/6,022×10²³=2 moli
