Given the equilibrium constant values:
N2 + 1/2O2 >>> N2O ; kc = 2.7 * 10^-18
N2O4>>>>2NO2 kc=4.6*10^-3
1/2N2 + O2>>>NO2 kc = 4.1 * 10^-9
What is a value of Kc for this reaction?
2N2O + 3O2 >>> 2N2O4
equation 1 x 2 and reverse. (1/K12)
equation 2 x 2 and reverse. (1/K22)
equation 3 x 4 as written. (K34 )
Kc = (1/K12)*(1/K22)*(K34) = ??
Check my work. Make sure the equations you have added together gets the equation you want at the end. I think this will do it. I've tried to write superscripts and subscripts but if I missed one of the "turn ons or turn offs" it will be messed up. I'll correct it if it appears to be too difficult to decipher.
i got 2.72 * 10^17, and got it wrong. i reversed the first by taking the reciprocal, and reversed the 2nd one, times 2 by the last one. added them, square rooted and then doubled. what did i do wrong
High school teacher
To find the value of Kc for the reaction 2N2O + 3O2 >>> 2N2O4, we can use the equilibrium constant expressions for the given reactions and multiply them together based on the stoichiometric coefficients.
The given equilibrium constants are:
1. N2 + 1/2O2 >>> N2O ; kc = 2.7 * 10^-18
2. N2O4 >>> 2NO2 ; kc = 4.6 * 10^-3
3. 1/2N2 + O2 >>> NO2 ; kc = 4.1 * 10^-9
Let's combine these equilibrium constants to get the desired one:
First, let's notice that the second reaction gives us the equilibrium constant for the reverse of the reaction we are interested in. We need to flip the equation to obtain the Kc value for the forward reaction:
2NO2 >>> N2O4; kc for the forward reaction = 1/kc = 1/(4.6 * 10^-3)
Now, let's combine the expressions for the forward reactions of the three given equilibrium constants to get the expression for the desired reaction:
N2 + 1/2O2 + 1/2N2 + O2 >>> 2NO2
Since addition of multiple equations leads to the multiplication of their equilibrium constants, we can multiply the given equilibrium constants as follows:
kc_desired = (kc_1)^(1/2) * (kc_2)^(1/2) * (kc_3)^(2/3)
Substituting the given values:
kc_desired = (2.7 * 10^-18)^(1/2) * (1/(4.6 * 10^-3))^(1/2) * (4.1 * 10^-9)^(2/3)
kc_desired = 1.67 * 10^-9
Therefore, the value of Kc for the reaction 2N2O + 3O2 >>> 2N2O4 is 1.67 * 10^-9.