Răspuns:
MC3H7NO2=3×12+7×1+14+2×16=89g/mol
89g C3H7NO2...........36gC.....7gH.....14gN.......32gO
100gC3H7NO2..........xgC.......ygH......zgN.........tgO
x=100×36/89=calculeaza
y=100×7/89=calculeaza
z=100×14/89=calculeaza
t=100×32/89=calculeaza
Explicație: