Question

Now suppose a reaction vessel is filed with 1.98 atm of dintrogen tetroxide (N-04) at 341. "C. Answer the following questions about this system fall ts it possible to reverse this tendency by adding NO2 In other words, If you said the pressure of N 0, will tend to rise, can that be changed to a tendency to fall by adding NO2? Similarty, it you said the pressure of N204 will tend to fall, can that be changed to a tendency to rise by adding NO. the minimum pressure of NO2 needed to reverse it 囗

Answer 1

We start with pure $N_2O_4$. Some of it will dissociate into to reach equilibrium.

Hence, the pressure of $N_2O_4$ will fall. If we add some , it will associate to form $N_2O_4$.

This will increase the pressure of $N_2O_4$. This will reverse the tendency.

$\\ \: \\ \: \Delta G^0 = -5.4 \: kJ = -5400 \: J \\ \: \\ \: \Delta G^0 = -RTlnK \\ \: \\ \: -5400 \: J = -8.314 \: J/mol/K \times (341.+273) \: K \times lnK \\ \: \\ \: lnK=1.058 \\ \: \\ \:K=2.88$

$\\ \: \\ \:K= \dfrac { P_{N2O4} }{ P_{NO2}^2 } \\ \: \\ \: 2.88=\dfrac { 1.98 }{ P_{NO2}^2 } \\ \: \\ \:P_{NO2}^2 = 0.688 \\ \: \\ \:P_{NO2}=0.829$

When the pressure of NO2 exceeds, the tendency can be reversed.

Consider the following equilibrium: Now suppose a reaction vessel is filled with 1.98 atm of dinitrogen tetroxide (N204) at 341 ℃. o rise Under these conditions, will the pressure of N204 tend to rise or fall 2410 ts it possible to reverse this tendency by adding NO2 In other words, If you said the pressure of N204 will tend to rise, can that be changed to a tendency to fall by adding NO2? Similarly, if you said the pressure of N204 will tend to fall, can that be changed to a tendency to rise by adding NO2 If you said the tendency can be reversed in the second question, calculate the minimum pressure of NO2 needed to reverse it. Round your answer to 2 significant digts