Answer :
Answer:201.9 grams
Explanation:
To determine how many grams of Cl₂ will be produced along with 250.0 kJ of heat in the given reaction, we need to follow these steps:
1. **Understand the reaction and its enthalpy change:**
The given reaction is:
\[
\text{PCl}_5(g) + 87.9 \, \text{kJ} \rightarrow \text{PCl}_3(g) + \text{Cl}_2(g)
\]
This indicates that 87.9 kJ of heat is required to produce 1 mole of Cl₂.
2. **Calculate the number of moles of Cl₂ produced with 250.0 kJ of heat:**
Using the given enthalpy change, we can set up a proportion to find the moles of Cl₂ produced by 250.0 kJ of heat:
\[
\frac{1 \text{ mole of Cl}_2}{87.9 \, \text{kJ}} = \frac{n \, \text{moles of Cl}_2}{250.0 \, \text{kJ}}
\]
Solving for \(n\):
\[
n = \frac{250.0 \, \text{kJ}}{87.9 \, \text{kJ/mole}}
\]
\[
n \approx 2.844 \, \text{moles of Cl}_2
\]
3. **Convert moles of Cl₂ to grams:**
The molar mass of Cl₂ is calculated as follows:
- The atomic mass of Cl (chlorine) is approximately 35.5 g/mol.
- Since Cl₂ consists of two chlorine atoms, its molar mass is \( 2 \times 35.5 \, \text{g/mol} = 71.0 \, \text{g/mol} \).
Now, we convert moles to grams:
\[
\text{Mass of Cl}_2 = n \times \text{molar mass of Cl}_2
\]
\[
\text{Mass of Cl}_2 = 2.844 \, \text{moles} \times 71.0 \, \text{g/mol}
\]
\[
\text{Mass of Cl}_2 \approx 201.964 \, \text{g}
\]
Therefore, approximately 201.964 grams of Cl₂ will be produced along with 250.0 kJ of heat in the given reaction.
