Question

Under appropriate conditions, nitrogen and hydrogen undergo a combination reaction to yield ammonia: N2 (g) + 3H2 (g) → 2NH3 (g) A 9.3-g sample of hydrogen requires ________ g of N2 for a complete reaction.

Answer 1

Answer:

43 g N₂

Explanation:

To find the mass of N₂ required, you need to (1) convert grams H₂ to moles H₂ (via molar mass), then (2) convert moles H₂ to moles N₂ (via mole-to-mole ratio from equation coefficients), and then (3) convert moles N₂ to grams N₂ (via molar mass). It is important to arrange the conversions in a way that allows for the cancellation of units. The final answer should have 2 sig figs to match the amount of sig figs of the given value.

Molar Mass (H₂): 2(1.008 g/mol)

Molar Mass (H₂): 2.016 g/mol

Molar Mass (N₂): 2(14.009 g/mol)

Molar Mass (N₂): 28.018 g/mol

1 N₂(g) + 3 H₂(g) -----> 2 NH₃(g)

9.3 g H₂           1 mole             1 mole N₂             28.018 g
--------------  x  ----------------  x  --------------------  x  ------------------  =  43 g N₂
                        2.016 g            3 moles H₂            1 mole