Given the equilibrium constant values:

Question

1.N2(g)+ 1/2O2(g)<---> N2O(g)
KC=2.7*10^{-18}

2.N2O4(g)<----> 2NO2(g)
KC= 4.6*10^{-3}

3. 1/2N2(g)+ O2(g)<----> NO2(g)
KC=4.1*10^{-9}

-----------------------------
2N2O(g)+ 3O2 (g) <----> 2N2O4(g)

I need help i dunt know what to do next Part:

1.2N2(g)+ O2(g)<---> 2N2O(g) (*2)
KC=5.4*10^{-18}

2.2NO2<----> N2O4(g)
KC= 1/4.6*10^{-3}

I know i flip the second equation so Kc is flipped over 1...and i multiplied the 1st equation by 2:

Now i don't know what to do i don't know how they got to the final equation.

Answer 1

I'm so very lost

Answer 2

Reverse 1.
Multiply 3 by 2.
Reverse 2.
Add the equations and you get 1/2 of the equation you want (if I didn't goof), then double that (and square the resulting K).

Answer 3

Teacher