Question

To what temperature does a 250 ml cylinder containing 0.40 grams of helium gas need to be collected in order for the pressure to be 253.25 kPa?

Please show work.

Answer 1

T =76.13 K

Step-by-step explanation:

Given data:

Temperature of gas = ?

Volume of gas = 250 mL(250/1000 = 0.25 L)

Mass of helium = 0.40 g

Pressure of gas = 253.25 kpa (253.25/101 = 2.5 atm)

Solution:

Formula:

PV = nRT

First of all we will determine the number of moles of helium.

Number of moles = mass/ molar mass

Number of moles = 0.40 g/ 4 g/mol

Number of moles = 0.1 mol

Now we will put the values.

R = general gas constant = 0.0821 atm.L/ mol.K

T = PV/nR

T =2.5 atm× 0.25 L /0.1 mol ×0.0821 atm.L/ mol.K

T = 0.625 /0.00821/K

T =76.13 K