Question

131.0 g of chlorine gas (Cl2) and 35.0 g of helium (He) are mixed in agcontainer with a total pressure of 1,859. mmHg. Determine the partialpressure of helium gas.Answer:mmHg

Answer 1

Answer:

$1,535.28\text{ mmHg}$

Explanation:

Here, we want to get the partial pressure of the Helium gas

To get this, we need to know the mole fraction of each of the gases

To get the number of moels of chlorine gas, we have to divide the mass of the chlorine gas by its molar mass

The molar mass of the chlorine gas is 71 g/mol

Thus, we have the number of moles as:

$\frac{131}{71}\text{ = 1.845 moles}$

For the Helium, we have to divide the mass given by the atomic mass

The atomic mass of helium is 4 amu

Thus, we have the number of moles as:

$\frac{35}{4}\text{ = 8.75 moles}$

According to Dalton's law of partial pressure, the total pressure is the sum of the individual partial pressure

We can get the mole fraction of the helium by dividing the number of moles of the helium by the total number of moles

We have the partial pressure as:

$\frac{8.75}{8.75\text{ + 1.845}}\times\text{ 1,859 = 1,535.28 mmHg}$