Chemistry 340 Physical Chemistry for Biochemists
- One mole of nitrogen is allowed to expand from 0.5 to 10 L. Calculate the change in entropy using the ideal gas law.
- (a) Integrate the Gibbs-Helmholtz equation to obtain an expression for ∆G2 at temperature T2 in terms of ∆G1 at 1 T , assuming ∆H is independent of temperature.
(b) Obtain an expression for ∆G2 using the more accurate approximation that
∆ =∆ + − ∆ H H TT C 1 1 ( ) P where T1 is an arbitrary reference temperature.
- When a liquid is compressed its Gibbs energy is increased. To a first approximation the increase in molar Gibbs energy can be calculated using (/) , GP V T ∂∂ = assuming a constant molar volume. What is the change in the molar Gibbs energy for liquid water when it is compressed to 1000 bar?
- An ideal gas is allowed to expand reversibly and isothermally (25 °C) from a pressure of 1 bar to a pressure of 0.1 bar. (a) What is the change in molar Gibbs energy? (b) What would be the change in molar Gibbs energy if the process occurred irreversibly?
- Helium is compressed isothermally and reversibly at 100 °C from a pressure of 2 to 10 bar. Calculate (a) q per mole, (b) w per mole, (c) ∆G, (d) ∆A, (e) ∆H, (f) ∆U, and (g) ∆S , assuming helium is an ideal gas.
- Toluene is vaporized at its boiling point, 111 °C. The heat of vaporization at this temperature is 1 361.9J g . − For the vaporization of toluene, calculate (a) w per mole, (b) q per mole, (c) ∆H, (d) ∆U, (e) ∆G, and (f) ∆S.
