Answer: 351.19K
Explanation: This is a case were the combined gas equation can be applied.
Combined gas equation is given as; P1V1/T1 = P2V2/T2,
where P1 = Initial pressure = 2.50 atm
P2= Final pressure = 7.50 atm
V1 = Initial volume = 3.50L
V2 = Final Volume = 1.50L
T1 = Initial Temperature = 273.15K
T2 = Final Temperature = ?
∴ 2.50atm x 3.50L / 273.15K = 7.50atm x 1.50L / T2
Making T2 the subject of Formular; we then have;
T2 = P2 V2 T1 / P1 V1 = 7.50atm x 1.50L x 273.15K / 2.50atm x 3.50L
= 3072.94 / 8.75 = 351.19K
The change in temperature (T2) is 351.19K.