Question

The amount of heat supplied to `4xx10^(-2)` kg of nitrogen at room temperature to rise its temperature by `50^(@)C` at constant pressure is (Molecualr mass of nitrogen is 28 and `R= 8.3 J mol^(-1)K^(-1))`
A. 2.08 KJ
B. 3.08 KJ
C. 4.08 KJ
D. 5.08 KJ

Answer 1

Correct Answer - A
Given , `m=4xx10^(-2)kg =40 g. DeltaT=50^(c )`
Number of moles ,`n=(m)/(M)=(40)/(28)=1.43`
As nitrogen is a diatomic gas, molar specific heat at contstant pressure is
`C_(p)=(7)/(2)R=(7)/(2)xx8.3 J mol^(-1) K^(-1)=29.05 J mol^(-1) K^(-1)`
As `DeltaQ =nC_(p)DeltaT`
`DeltaQ=1.43xx29.05xx50=2.08xx10^(3)` J =2 2.08KJ