A 8.0 L sample at 25•C and 1.00 atm of pressure contains 0.5 moles of gas. If an additional 0.75 moles of gas at the same pressure and temperature are added, what is the final total volume of the gas?

The final total volume of the gas is 20 L

Explanation:

According to the Avogadro's law, the volume of gas is directly proportional to the number of moles of gas at same pressure and temperature. That means

or,

where,

= initial volume of gas = 8.0 L

= final volume of gas = ?

= initial moles of gas = 0.5 moles

= final moles of gas = 0.5 + 0.75 = 1.25 moles

Putting in the values , we get:

The final total volume of the gas is 20 L