Can someone please answer this question

Question

Given the following equation:

2 N₂ (g) + 3 H₂ (g) → 2 NH₃ (g)

How many grams of H₂ are required if 35 grams of N₂ reacts? 

 ________g H₂

Answer 1

2N₂(g) + 3H₂(g) ==> 2NH₃(g) ... balanced equation

Look at the coefficients int he balanced equation. You see that 2 mols N₂ reacts with 3 mols H₂. So, we need to convert the 35 g N₂ to mols.

35 g N₂ x 1 mol N₂ / 28 g = 1.25 mols N₂ is reacting.

How many moles of H₂ will that require?

Use the mol ratios in the balanced equation fo find out.

1.25 mols N₂ x 3 mols H₂ / 2 mol N₂ = 1.875 mols H₂ required

Now convert this to grams

1.875 mols H₂ x 2 g H₂ / mol = 3.75 g H₂ = 3.8 g H₂ (2 sig. figs.)