The Keq for the equilibrium below is 5.4 × 1013 at 480.0 °C.

2NO (g) + O2 (g) ↔ 2NO2 (g)

What is the value of Keq at this temperature for the following reaction?

NO2 (g) ↔ NO (g) + 1/2 O2 (g)
The Keq for the equilibrium below is 5.4 × 1013 at 480.0 °C.

2NO (g) + O2 (g) ↔ 2NO2 (g)

What is the value of Keq at this temperature for the following reaction?

NO2 (g) ↔ NO (g) + 1/2 O2 (g)

a. 5.4 × 1013
b. 5.66 × 10-3
c. 5.4 × 10-13
d. 1.4 × 10-7
e. none of the above

D

the Keq expression of the 2nd one is = to (1/the first Keq expression)^(1/2)

so take the answer of the first Keq, 5.4x10^13 and put it in that equation

(1/(5.4x10^13))^(1/2)=1.36x10^-7=1.4x10^-7

Well, it seems like we're playing with equilibrium constants here! Let's see if we can figure out the value for the Keq of this reaction.

The given reaction can be written as:

2NO2 (g) ↔ NO (g) + 1/2 O2 (g)

Now, here comes the fun part! Remember that Keq is defined as the ratio of the products' concentrations to the reactants' concentrations, with each raised to their respective stoichiometric coefficients.

In this case, since we want the Keq for the given reaction, we need to determine the expression using the stoichiometric coefficients from the balanced equation. Let's give it a go:

Keq = [NO] * [O2]^(1/2) / [NO2]^2

Now, we also know that Keq for the first reaction is 5.4 × 10^13 at 480.0 °C. Since the given reaction is the reverse of the first reaction, we can simply reciprocate the value:

Keq(reverse) = 1 / Keq(forward)

So, Keq(reverse) = 1 / (5.4 × 10^13) = 1.852 × 10^-14

Now, let's look at the answer choices:

a. 5.4 × 10^13
b. 5.66 × 10^-3
c. 5.4 × 10^-13
d. 1.4 × 10^-7
e. none of the above

If we compare the calculated Keq(reverse) value (1.852 × 10^-14) with the answer choices, we can see that none of them match! So, the correct answer is e. none of the above.

Remember, chemistry can be fun, even when the answers don't match up! Keep up the good work, and keep those chemical reactions balanced!

To find the value of Keq for the given reaction, we can use the fact that the value of Keq for the reverse reaction is the reciprocal of the Keq for the forward reaction.

The Keq for the forward reaction is 5.4 × 10^13.

Therefore, the Keq for the reverse reaction is 1/(5.4 × 10^13).

The given reaction is:
NO2 (g) ↔ NO (g) + 1/2 O2 (g)

Comparing this reaction to the reverse reaction of the given Keq,
the coefficients of NO2 and NO are the same, but the coefficient of O2 is different (1/2 vs 1).
Therefore, the value of Keq for the given reaction is equal to the Keq for the reverse reaction raised to the power of the coefficient of O2.

Keq for the given reaction = [Keq(forward reaction)]^(coefficient of O2)

Keq for the given reaction = [1/(5.4 × 10^13)]^(1/2)

Keq for the given reaction = (5.4 × 10^13)^(-1/2)

Keq for the given reaction = 1/(5.4 × 10^13)^(1/2)

Keq for the given reaction = 1/(√5.4 × 10^13)

Calculating this value, we find that it is approximately equal to 5.66 × 10^-7.

Therefore, the value of Keq at this temperature for the given reaction is option b. 5.66 × 10^-7.

To find the value of Keq for the given reaction, we can use the concept of equilibrium expressions.

The equilibrium constant (Keq) is the ratio of the product concentrations to the reactant concentrations at equilibrium. For the given reaction:

NO2 (g) ↔ NO (g) + 1/2 O2 (g)

The equilibrium expression can be written as:

Keq = [NO] * [O2]^0.5 / [NO2]

Since the concentration of a pure solid or liquid is constant, we only include the concentrations of the gases in the equilibrium expression.

However, we can use the value of Keq and the given equilibrium to relate it to the desired equilibrium. We use the following relationship for the reverse reaction:

Keq_reverse = 1 / Keq_forward

So, for the given reaction:

Keq_reverse = 1 / (5.4 × 10^13)

The correct answer is to be selected from the given options. Let's check which option matches the calculated value:

a. 5.4 × 10^13: This is the value of Keq for the forward reaction, not the reverse. So, this option is incorrect.

b. 5.66 × 10^-3: This does not match the calculated value. So, this option is incorrect.

c. 5.4 × 10^-13: This matches the calculated value. So, this option is the correct answer.

d. 1.4 × 10^-7: This does not match the calculated value. So, this option is incorrect.

e. none of the above: Since option c matches the calculated value, none of the other options are correct. Therefore, this option is also incorrect.

The correct answer is c. 5.4 × 10^-13.