23. How much energy is required to heat 36.0 g H₂O from a liquid at 65°C to a gas at 115°C? The

following physical data may be useful.

AHvap -40.7 kJ/mol

Cliq-4.18 J/gºC

Cgas - 2.01 J/gºC

Csol-2.09 J/gºC

Tmelting -0°C

Tboiling - 100°C

24. How much energy must be removed from a 125 g sample of benzene (molar mass = 78.11 g/mol) at

425.0 K to liquify the sample and lower the temperature to 335.0 K? The following physical data may be

useful.

AHvap-33.9 kJ/mol

AHfus 9.8 kJ/mol

Cliq- - 1.73 J/gºC

Cgas-1.06 J/gºC

Csol-1.51 J/gºC

Tmelting - 279.0 K

Tboiling

-353.0 K

25. How much energy is required to heat 87.1 g acetone (molar mass- 58.08 g/mol) from a solid at

-154.0°C to a liquid at -42.0°C? The following physical data may be useful.

AHfus-7.27 kJ/mol