Question

20 ml of hydrogen measured at 15'c are heated to 35'c. What is the new volume at the same pressure?

Answer 1

V1= 20ml= 0.02L
T1= 15°C= 288K
V2=?
T2= 35°C= 308K

V1/T1= V2/T2
V2= V1xT2/T1
V2= 6.16/288
V2= 0.0213
V2= 21.3ml

Answer 2

Answer: 21.4 ml

Explanation: Charles' Law: This law states that volume is directly proportional to the temperature of the gas at constant pressure and number of moles.

$V\propto T$    (At constant pressure and number of moles)

$\frac{V_1}{T_1}=\frac{V_2}{T_2}$

where V = Volume

T= temperature in Kelvin

Given:  

$V_1=20 ml$

$T_1=15^0C=15+273K=288K$

$V_2=?$

$T_2=35^0C=35+273K=308K$

$\frac{20ml}{288K}=\frac{V_2}{308K}$

$V_2=21.4ml$