Question

How many grams of zinc metal are required to produce 2.00 liters of hydrogen gas at stp according to the chemical equation shown below? how many grams of zinc metal are required to produce 2.00 liters of hydrogen gas at stp according to the chemical equation shown below? 5.83 g 11.7 g 0.171 g 131 g?

Answer 1

Answer : 5.83 grams of Zinc metal are required to produce the given amount of H2.

Explanation :

The chemical equation for the reaction between zinc metal and hydrochloric acid is given below.

`Zn(s) + 2HCl(aq)\rightarrow ZnCl_(2)(aq)+ H_(2)(g)`

Step 1 : Find moles of H2.

Let us find out the moles of H2 gas produced at STP.

One mole of any gas occupies 22.4 L at STP.

`2L H_(2)* (1mol)/(22.4 L)= 0.0893 mol`

Step 2 : Find moles of Zn.

The mole ratio of Zn and H2 is 1 : 1 .

Therefore the moles of Zn required to produce the given amount of H2 are 0.0893 mol.

Step 3 : Convert mol Zn to grams.

Convert the above moles to grams using molar mass of Zn.

`0.0893molZn* (1mol)/(65.38g)= 5.83g`

5.83 grams of Zinc metal are required to produce the given amount of H2.