Question

H2 + Br2 → 2HBr If 2.23 g of hydrogen (H2) reacts completely, how many grams of hydrogen bromide (HBr) is formed? (mw Br=79.9) Question 16 options: A) 2.21 g of HBr B) 179 g of HBr C) 82.13 g of HBr D) 80.92 g of HBr

Answer 1

Answer:

The correct option is;

B) 179 g

Explanation:

The parameters given are;

Mass of H₂ that takes part in the reaction = 2.23 g

Molar mass of hydrogen gas, H₂ = 2.016 g

Number of moles, n, of hydrogen gas H₂ is given by the relation;

$n = \dfrac{Mass \ of \ hydrogen \ gas, \, H_2 }{Molar \ mass \ of \, H_2 } = \dfrac{2.23}{2.016} = 1.106 \ moles$

Chemical equation for the reaction;

H₂ + Br₂ → 2HBr

Given that one mole of H₂ reacts with one mole of Br₂ to produce two moles of HBr

1.106 mole of H₂ will react with 1.106 mole of Br₂ to produce 2 × 1.106 which is 2.212 moles of HBr

The molar mass, of HBr = 80.91 g/mol

The mass of HBr produced = Molar mass of HBr × Number of moles of HBr

The mass of HBr produced = 80.91 × 2.212 = 178.997 g ≈ 179 grams

Therefore, the correct option is B) 179 g.