Given:
[tex]\[ \text{CaC}_2 + \text{N}_2 \rightarrow \text{CaCN}_2 + \text{C} \][/tex]

In this chemical reaction, how many grams of [tex]\(\text{N}_2\)[/tex] must be consumed to produce 265 grams of [tex]\(\text{CaCN}_2\)[/tex]? Express your answer to three significant figures.

The reaction requires [tex]\(\qquad\)[/tex] grams of [tex]\(\text{N}_2\)[/tex].



Answer :

To determine how many grams of [tex]\( N_2 \)[/tex] must be consumed to produce 265 grams of [tex]\( CaCN_2 \)[/tex], we will follow these steps:

1. Determine the molar mass of [tex]\( CaCN_2 \)[/tex] and [tex]\( N_2 \)[/tex]:
- The molar mass of [tex]\( CaCN_2 \)[/tex] is given as 80.1 g/mol.
- The molar mass of [tex]\( N_2 \)[/tex] is given as 28.0 g/mol.

2. Calculate the moles of [tex]\( CaCN_2 \)[/tex] produced:
- Mass of [tex]\( CaCN_2 \)[/tex] produced = 265 grams.
- To find the moles of [tex]\( CaCN_2 \)[/tex], use the formula:
[tex]\[ \text{Moles of } CaCN_2 = \frac{\text{Mass of } CaCN_2}{\text{Molar mass of } CaCN_2} \][/tex]
[tex]\[ \text{Moles of } CaCN_2 = \frac{265 \, \text{g}}{80.1 \, \text{g/mol}} \approx 3.308 \][/tex]

3. Relate the moles of [tex]\( CaCN_2 \)[/tex] to the moles of [tex]\( N_2 \)[/tex]:
- From the balanced equation, 1 mole of [tex]\( N_2 \)[/tex] produces 1 mole of [tex]\( CaCN_2 \)[/tex].
- Therefore, the moles of [tex]\( N_2 \)[/tex] required are equal to the moles of [tex]\( CaCN_2 \)[/tex] produced:
[tex]\[ \text{Moles of } N_2 = \text{Moles of } CaCN_2 \approx 3.308 \][/tex]

4. Calculate the mass of [tex]\( N_2 \)[/tex] required:
- To find the mass of [tex]\( N_2 \)[/tex], use the formula:
[tex]\[ \text{Mass of } N_2 = \text{Moles of } N_2 \times \text{Molar mass of } N_2 \][/tex]
[tex]\[ \text{Mass of } N_2 = 3.308 \, \text{moles} \times 28.0 \, \text{g/mol} \approx 92.634 \, \text{g} \][/tex]

So, the reaction requires approximately 92.634 grams of [tex]\( N_2 \)[/tex]. Rounding to three significant figures, the answer is:

The reaction requires [tex]\( 92.6 \)[/tex] grams of [tex]\( N_2 \)[/tex].