Hydrogen gas is prepared in the laboratory by reacting dilute HCl with granulated zinc.Following reaction takes place
Zn++2HCl------->ZnCl 2
+H2
Calculate the volume of H2 gas liberated at stp when 32.65 g of zn reacts with HCl(Zn=65.3g)
Zn+HCl→ ZnCl2+H2
From the equation it is clear that 1 mole of Zn react with 1 mole HCl to produce 1 mole H2.
Number of moles in 32.65 g Zn= 32.65/ molar mass of Zn =32.65/65.4=0.499
1 mole Zn→ 1mole H2
0.499 mole Zn→0.499 mole H2
At STP volume of 1 mole H2= 22.4L
so volume of 0.299 mole H2= 0.499 X 22.4 =11.176L