chemistry problem, should i use Q or K?

Question

Consider the following galvanic cell at 25°C.

Pt | Cr2+ (0.21 M), Cr3+ (2.4 M) || Co2+ (0.34 M) | Co
The overall reaction and equilibrium constant value are given below.

2 Cr2+(aq) + Co2+(aq) 2 Cr3+(aq) + Co(s) K = 2.79 107
Calculate the cell potential, , for this galvanic cell and G for the cell reaction at these conditions.

i was given K and the Molarity to find Q

i was thinks of this equation
Ecell= 0.0591/2 moles log Q
can someone show me if i am starting problem the right way or the wrong way.
hope someone can assist me in figuring this out. i don't mind if you guy can give me the website with this same of sample question, that would also help.
thanks

Answer 1

Just use the Nernst eqn.