Răspuns:
MCuCO3=64+12+3×16=124g/mol
124gCuCO3.................64gCu.............12gC.................48gO
100gCuCO3....................xgCu............ygC...................zgO
x=100×64/124=calculeaza
y=100×12/124=calculeaza
z=100×48/124=calculeaza
Explicație: