How much nitrogen is required to fully consume 11.8g of hydrogen?

Method 1 :

Molar mass of N₂ = 14.0 × 2 g/mol = 28.0 g/mol
Molar mass of H₂ = 1.0 × 2 g/mol = 2.0 g/mol

Balanced equation for the reaction:
N₂ + 3H₂ → 2NH₃
Mole ratio N₂ : H₂ = 1 : 3

No. of moles of H₂ consumed = (11.8 g) / (2.0 g/mol) = 5.9 mol
No. of moles of N₂ required = (5.9 mol) × (1/3) = 5.9/3 mol
Mass of N₂ required = (5.9/3 mol) × (28.0 g/mol) = 55.1 g

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Method 2 :

(11.8 g H₂) × (1 mol H₂ / 2.0 g H₂) × (1 mol N₂ / 3 mol H₂) × (28.0 g N₂ / 1 mol N₂)
= 55.1 g N₂

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Method 3 :

Mole ratio N₂ : H₂ = 1 : 3
Mass ratio N₂ : H₂ = (1 × 28) : (3 × 2) = 28 : 6

Mass of N₂ required = (11.8 g) × (28/6) = 55.1 g