To find the temperature of the gas when its volume is changed to 80ml at constant pressure, we can use the combined gas law equation:
(P1 × V1) / T1 = (P2 × V2) / T2
where:
P1 = initial pressure of the gas
V1 = initial volume of the gas
T1 = initial temperature of the gas
P2 = final pressure of the gas
V2 = final volume of the gas
T2 = final temperature of the gas (what we want to find)
Given:
P1 = 740 mm
V1 = 100 ml
T1 = 27°C = 27 + 273 = 300 Kelvin
P2 = 740 mm (constant pressure)
V2 = 80 ml
Plugging in the given values into the equation, we get:
(740 × 100) / 300 = (740 × 80) / T2
Simplifying the equation:
74000 / 300 = 59200 / T2
Cross multiplying:
74000 × T2 = 300 × 59200
Dividing both sides by 74000:
T2 = (300 × 59200) / 74000
Calculating T2:
T2 = 240
Therefore, the temperature of the gas will be 240 Kelvin when its volume is changed to 80ml at constant pressure.