5 moles of an ideal gas at 100 k are allowed to undergo reversible compression till its temperature becomes 200 k. if cy = 28 jk⁻¹ mol⁻¹ , calculate ∆AU and ∆PV for this process. (r = 8.0 jk⁻¹ mol⁻¹ )
A. ∆U = 14kJ ; ∆(pV) = 18kJ
B. ∆U = 14kJ ; ∆(pV) = 4kJ
C. ∆U = 2.8kJ ; ∆(pV) = 0.8kJ
D. ∆U = 14kJ ; ∆(pV) = 0.8kJ