Question

A reaction between liquid reactants takes place at - 11.0 degree C in a sealed, evacuated vessel with a measured volume of 45.0 L. Measurements show that the reaction produced 35. g of chlorine pentafluoride gas. Calculate the pressure of chlorine pentafluoride gas in the reaction vessel after the reaction. You may ignore the volume of the liquid of reactants. Be sure your answer has the correct number of significant digits.

Answer 1

Explanation:

The given data is as follows.

       T = $11^{o}C$ = (11 + 273) K = 284 K,     V = 45.0 L

      m = 35 g

As molar mass of chlorine pentafluoride is 130.445 g/mol. Hence, number of moles of chlorine pentafluoride are as follows.

      No. of moles = $\frac{mass}{\text{molar mass}}$

                             = $\frac{35 g}{130.445 g/mol}$

                             = 0.268 mol

Now, using the ideal gas equation we will find the pressure as follows.

                          PV = nRT

       $P \times 45.0 L = 0.268 mol \times 0.082 L atm/mol K \times 284 K$

                       P = 0.139 atm

Thus, we can conclude that pressure of chlorine pentafluoride gas in the given reaction vessel after the reaction is 0.139 atm.