Question

It is found that on heating a gas its volume increases by 50% and its pressure decreases to 60% of its original value. If the original temperature was −15°C, find the temperature to which it was heated.

Answer 1

Let the original volume (V) = 1 and

the original pressure (P) = 1 and

the temperature given (T) = −15°C.

= −15 + 273

= 258 K

V₁ or new volume after heating = original volume + 50% of original volume

= `1 + 1 xx 50/100`

= `1 + 1/2`

= `3/2`

P₁ or decreased pressure = 60%

`1 xx 60/100 = 0.6`

T₁ = to be calculated

`(PV)/T = (P_1 V_1)/T_1`

`(1 xx 1)/258 = 3/2 xx 0.6/T_1`

T₁ = 232.2

T₁ = 232.2 − 273

= −40.8°C