Question

Va rog ajutati-ma !!!!!

1 . Determinati numarul de moli existenti in : 4 g CO₂ , 25 g CaCO₃

2. Determinati cate grame reprezinta 1/4 moli O₂ , 2,5 moli MgO

Answer 1

a) 
μ CO2 = 12 + 32 = 44 g/mol
μ CaCO3 = 100 g/mol
n = m / μ 
n CO2 = 4 / 44 = 0.09 moli
n CaCO3 = 25/100 = 0.25 moli
b) 
μ O2 = 32 g/mol
μ MgO = 40 g/mol
m = n x μ 
m O2 = 1/4 x 32 = 8g;
m MgO = 2.5 x 40 = 100g