Advertisements
Advertisements
Question
Calculate a) ΔG°and b) the equilibrium constant for the formation of NO2 from NO and O2 at 298 K
\[\ce{NO(g) + 1/2 O_2 (g) <=> NO_2(g)}\]
where ΔfG⊝ (NO2) = 52.0 kJ/mol
ΔfG⊝ (NO) = 87.0 kJ/mol
ΔfG⊝ (O2) = 0 kJ/mol
Advertisements
Solution
a) For the given reaction,
ΔG⊝ = ΔG⊝ ( Products) – ΔG°( Reactants)
ΔG⊝ = 52.0 – {87.0 + 0}
= - 35.0 kJ mol–1
b) We know that,
ΔG⊝ = RT log Kc
ΔG⊝ = 2.303 RT log Kc
`"K"_"c" = (-35.5xx10^(-3))/(-2.303xx8.314xx298)`
= 6.134
`therefore "K"_"c" = "antilog" (6.134)`
`= 1.36 xx 10^6`
Hence, the equilibrium constant for the given reaction Kc is 1.36 × 106
APPEARS IN
RELATED QUESTIONS
Write the expression for the equilibrium constant, Kc for each of the following reactions:
\[\ce{2NOCl (g) ⇌ 2NO (g) + Cl2 (g)}\]
Write the expression for the equilibrium constant, Kc for the following reactions:
\[\ce{2Cu(NO3)2 (s) ⇌ 2CuO (s) + 4NO2 (g) + O2 (g)}\]
Write the expression for the equilibrium constant, Kc for the following reactions:
\[\ce{CH3COOC2H5(aq) + H2O(l) ⇌CH3COOH (aq) + C2H5OH (aq)}\]
Write the expression for the equilibrium constant, Kc for following reactions:
\[\ce{Fe^{3+}(aq) + 3OH^-(aq) ⇌ Fe(OH)3(s)}\]
Does the number of moles of reaction products increase, decrease or remain same when each of the following equilibria is subjected to a decrease in pressure by increasing the volume?
\[\ce{3Fe (s) + 4H2O (g) ⇌ Fe3O4 (s) + 4H2 (g)}\]
The value of Kc for the reaction 3O2 (g) ↔ 2O3 (g) is 2.0 ×10–50 at 25°C. If the equilibrium concentration of O2 in the air at 25°C is 1.6 ×10–2, what is the concentration of O3?
For the reaction \[\ce{H2 (g) + I2 (g) ⇌ 2HI (g)}\], the standard free energy is ∆GΘ > 0. The equilibrium constant (K ) would be ______.
On increasing the pressure, in which direction will the gas phase reaction proceed to re-establish equilibrium, is predicted by applying the Le Chatelier’s principle. Consider the reaction.
\[\ce{N2 (g) + 3H2 (g) ⇌ 2NH3 (g)}\]
Which of the following is correct, if the total pressure at which the equilibrium is established, is increased without changing the temperature?
For the reaction : \[\ce{N2 (g) + 3H2 (g) ⇌ 2NH3 (g)}\]
Equilibrium constant `K_C = ([NH3]^2)/([N_2][H_2]^3)`
Some reactions are written below in Column I and their equilibrium constants in terms of Kc are written in Column II. Match the following reactions with the corresponding equilibrium constant
| Column I (Reaction) | Column II (Equilibrium constant) |
| (i) \[\ce{2N2 (g) + 6H2 (g) ⇌ 4NH3 (g)}\] | (a) `2K_c` |
| (ii) \[\ce{2NH3 (g) ⇌ N2 (g) + 3H2 (g)}\] | (b) `K_c^(1/2)` |
| (iii) \[\ce{1/2 N2 (g) + 3/2 H2 (g) ⇌ NH3 (g)}\] | (c) `1/K_c` |
| (d) `K_c^2` |
Match standard free energy of the reaction with the corresponding equilibrium constant.
| Column I | Column II |
| (i) ∆GΘ > 0 | (a) K > 1 |
| (ii) ∆GΘ > 0 | (b) K = 1 |
| (iii) ∆GΘ = 0 | (c) K = 0 |
| (d) K < 1 |
At 1990 K and 1 atm pressure, there are equal numbers of Cl2 molecules and Cl atoms in the reaction mixture. The value of Kp for the reaction Cl2(g) ⇌ 2Cl(g) under the above conditions is x × 10−1. The value of x is ______. (Rounded-off to the nearest integer)
For the reaction \[\ce{A(g) <=> B(g)}\] at 495 K, ΔG° = −9.478 kJ mol−1
If we start the reaction in a closed container at 495 K with 22 millimoles of A, the amount of B in the equilibrium mixture is ______ millimoles. (Round off to the Nearest Integer).
[R = 8.314 J mol−1 K−1; ln 10 = 2.303]
For which of the following Kp is less than Kc?
The value of Kc is 64 at 800 K for the reaction \[\ce{N2(g) + 3H2(g) <=> 2NH3(g)}\].
The value of Kc for the following reaction is:
\[\ce{NH3(g) <=> 1/2N2(g) + 3/2H2(g)}\]
A solid XY kept in an evacuated sealed container undergoes decomposition to form a mixture of gases X and Y at temperature T. The equilibrium pressure is 10 bar in the vessel. Kp for this reaction is ______.
