Question

Cati litri de hidrogen se obtin in urma reactiei dintre 4,8 grame de Mg si o cantitate de HCl

Answer 1

Mg + 2 HCl => MgCl2 + H2 
m Mg = 4.8 g
M Mg = 24.3 g/mol 
n = m/M => n Mg = 4.8 / 24.3 = 0.2 mol Mg
1 mol  Mg ... 2 mol HCl ... 1 mol H2
0.2 mol Mg ...x mol HCl ...y mol H2
x=0.2 * 2 / 1= 0.4 mol HCl
y=0.2 *1 / 1 = 0.2 mol H2
V = n * 22.4 L/mol 
V H2 = n H2 * 22.4 L/mol =  0.2 * 22.4 = 4.48 L H2 cn