21480.The enthalpy of vaporization of benzene is +35.3 kJ/mol at its boiling point of 80°C. The entropy change in the transition of vapour to liquid at its boiling point is ______. (in J mol–1 K–1)
–100
+100
+342
–342
21481.ΔHvap = 30 KJ/mole and ΔSvap = 75 Jmol–1K–1. Find temperature of vapour, at one atmosphere
400 K
350 K
298 K
250 K
21482.Standard entropy of X2, Y2 and XY3 are 60, 40 and 50 JK–1mol–1, respectively. For the reaction, $\dfrac{1}{2}$X2 + $\dfrac{3}{2}$Y2 → XY3, ΔH = –30 kJ, to be at equilibrium, the temperature will be
1250 K
500 K
750 K
1000 K
21483.The temperature of the system decreases in an ______.
adiabatic compression
isothermal expansion
isothermal compression
adiabatic expansion
21484.Which of the following is an intensive property?
temperature
surface tension
viscosity
all of these