Answer: Final pressure of the gas is 0.916atm
Explanation: Using Charles law formula. P1V1T2 = P2V2T1
Where P1 = 0.991atm, V1 = 0.0255L, T1 = 69°C = 273+69= 546.15 , P2 = x, V2 = 0.0255L, T2 = 43°C = 273+43= 316.15K.
Solution.
Substituting all the parameters into the equation
P1V1T2=P2V2T1,
we get,
0.991×0.0255×316.15 = P2 × 0.0255 × 546.15
P2 = 0.916atm