Question

The amount of HCl formed when 8 g of hydrogen
gas (H2) reacts with 142 g of chlorine gas (C12)
is (Atomic mass of Cl = 35.5 u)
H2 + Cl2 → 2 HCI​

Answer 1

Answer :-

146 grams of HCl is formed.

Explanation :-

The balanced chemical equation for the reaction is :-

H₂ + Cl₂ → 2HCl

Moles of H₂ :-

= Given Mass/Molar mass

= 8/2

= 4 moles

Moles of Cl₂ :-

= Given Mass/Molar mass

= 142/71

= 2 moles

________________________________

We have less moles of Cl₂ than H₂.

Thus, Cl₂ is the limiting reagent and will control the amount of product.

Now, according to the balanced chemical equation :-

∵ 71g of Cl₂ → 73g of HCl

∴ 142 g of Cl₂ gives :-

⇒ (142 × 73/71)g of HCl

⇒ 146g of HCl

Answer 2

Required Answer :-

We may solve by

Moles of Hydrogen or H₂ =

Moles = Total Mass/Molar Mass

Moles = 8/2

Moles = 4/1

Moles = 4

Moles of CI₂ =

Moles = Total Mass/Molar Mass

Moles = 142/71

Moles = 2/1

Moles = 2

We have asked to find amount of HCI

142/71 × 73

2/1 × 73

2 × 73/1

146 g