In air standard Otto cycle the terminal pressures at the end of compression, heat release and expansion are P2, P3 and P4 respectively. If the corresponding values are P'2, P'3 and P'4, taking into account the effect to variable specific heat and dissociation of the working fluid, then
1
P2 < P'2 and P3 > P'3
2
P3 < P'3 and P4 > P'4
3
P2 < P'2, P3 > P'3 and P4 < P'4
4
P2 > P'2, P3 > P'3