Given:

CaC2 + N2 → CaCN2 + C

In this chemical reaction, how many grams of N2 must be consumed to produce 265 grams of CaCN2? Express your answer to three significant figures.

The reaction requires how many grams of N2?

92.6 g.

Explanation:

The balanced equation is:

CaC₂ + N₂ → CaCN₂ + C.

It is clear that 1.0 mole of CaC₂ reacts with 1.0 mole of N₂ to produce 1.0 mole of CaCN₂ and 1.0 mole of C. We need to calculate the no. of moles of 265.0 g of CaCN₂ produced using the relation:

n = mass / molar mass = (265.0 g) / (80.102 g/mol) = 3.308 mol.

We should get the no. of moles of N₂ needed to produce 3.308 mol of CaCN₂.

∵ 1.0 mole of N₂ produces → 1.0 mole of CaCN₂.

∴ 3.308 mole of N₂ produces → 3.308 mole of CaCN₂.

Now, we can get the grams of N₂ consumed to produce 265.0 g of CaCN₂:

∴ The grams of N₂ = n x molar mass = (3.308 mole) (28.0 g/mol) = 92.63 g = 92.6 g.