Problem I

Consider the dissociation of iodine I2(g)<=> 2 I (g). At 1473 K, kc= 0.0258, 20.0 g of an I2/I mixture exerts a pressure of 1.30 atm in a volume of 10.0L.

A) At the pressure of 1.30 atm what are the mole fractions the 2 gases in I2/I mixture?

B) After a certain period, the system reaches its equilibrium state, what is the pressure of the system at equilibrium?

(Hint: the molar mass of I2 = 253.8g/mol)

Problem II

For the following cell Al(s)|Al3+

(1.00 M || Be 2+ (1.0×10^-9) Be(s)

A) Write the overall net ionic equation

B) Calculate the cell potential Ecell at 25°C and predict the spontaneity of the overall reaction.

C) Calculate the cell potential Ecell at 300°C and predict the spontaneity of the overall reaction.

The standard reduction potentials are:

Al3 (aq) + 3e- -> Al (s) E°= -166 V

Be2+ + 2e- -> Be (s) E°=?