Question

A syringe containing 1.75 mL of oxygen gas is cooled from 97.8 ∘C to 0.7 ∘C. What is the final volume Vf of oxygen gas? (Assume that the pressure is constant.)

Answer 1

Answer : The final volume of oxygen gas will be, 1.292 ml

Explanation :

Charles' Law : It is defined as the volume of gas is directly proportional to the temperature of the gas at constant pressure and number of moles.

`V\propto T`

or,

`(V_1)/(V_2)=(T_1)/(T_2)`

where,

`V_1` = initial volume of oxygen gas = 1.75 ml

`V_2` = final volume of oxygen gas = ?

`T_1` = initial temperature of gas =
`97.8^oC=273+97.8=370.8K`

`T_2` = final temperature of gas =
`0.7^oC=273+0.7=273.7K`

Now put all the given values in the above formula, we get the final volume of the oxygen gas.

`(1.75ml)/(V_2)=(370.8K)/(273.7K)`

`V_2=1.292ml`

Therefore, the final volume of oxygen gas will be, 1.292 ml