In a chemical interaction 10 g of hydrogen chloride is added to 20 g of zinc to form 24 g of zinc chloride and a certain amount of hydrogen gas. What mass of hydrogen gas is expected to be formed?

Question

6 g
14 g
34 g
54 g

Answer 1

To answer this question, we need to use the law of conservation of mass. According to this law, the total mass of the reactants must be equal to the total mass of the products in a chemical reaction.

Given:
- Mass of hydrogen chloride (HCl) = 10 g
- Mass of zinc (Zn) = 20 g
- Mass of zinc chloride (ZnCl2) formed = 24 g

We need to calculate the mass of hydrogen gas (H2) formed.

To do this, we can subtract the total mass of the reactants (HCl and Zn) from the total mass of the products (ZnCl2 + H2).

Total mass of reactants = Mass of HCl + Mass of Zn = 10 g + 20 g = 30 g

Total mass of products = Mass of ZnCl2 + Mass of H2 = 24 g + Mass of H2

Now, we can use the law of conservation of mass to set up an equation:
Total mass of reactants = Total mass of products

30 g = 24 g + Mass of H2

Mass of H2 = 30 g - 24 g
Mass of H2 = 6 g

Therefore, the mass of hydrogen gas expected to be formed is 6 g.