Question 1

If K_c is the equilibrium constant for a forward reaction what is K_c' for the reverse reaction?

Accepted Answer

The equilibrium constant for the reverse reaction is the reciprocal of the equilibrium constant for the forward reaction, which is mathematically represented as the inverse of the forward reaction's equilibrium constant, hence (K_c)^-1.

Question 2

Write the equilibrium equation for the reverse reaction: 2 CH₄(g)+ 3 O₂(g)⇌ 2 CO(g)+ 4 H₂O(g)

Accepted Answer

A

Question 3

Which of the following statements is false regarding the equilibrium constant,K_c?

Accepted Answer

The equilibrium constant for the reverse reaction is the reciprocal, not the negative, of the equilibrium constant for the forward reaction.

Question 4

A mixture of carbon monoxide,hydrogen,and methanol is at equilibrium.The balanced chemical equation is: CO(g)+ 2 H₂(g)⇌ CH₃OH(g).At 250°C,the mixture contains 0.0960 M CO,0.191 M H₂,and 0.150 M CH₃OH.What is the value for K_c?

Accepted Answer

The answer of A mixture of carbon monoxide,hydrogen,and methanol is...

Question 5

What is true about the relationship of K_p and K_cfor the reaction: 2 CH₄(g)+ 3 O₂(g)⇌ 2 CO(g)+ 4 H₂O(g)?

Accepted Answer

K_p and K_c are equilibrium constants for the same reaction, but K_p is calculated for the forward reaction and K_c is calculated for the reverse reaction. Since the forward reaction is favored when the equilibrium constant is greater than 1, and the reverse reaction is favored when the equilibrium constant is less than 1, a higher value of K_p relative to K_c indicates that the forward reaction is favored, which means that more of the products will be formed at equilibrium. Therefore, K_p > K_c.

Question 6

Which statement about the equilibrium constant is true? The value of K_c

Accepted Answer

The equilibrium constant (K) is defined as the ratio of product concentrations to reactant concentrations at equilibrium for a given reaction at a specific temperature. Therefore, it only changes with temperature and not with changes in reactant or product concentrations. Hence, option C is the correct answer.

Question 7

If K_c is the equilibrium constant for a forward reaction,2 A⇌ B,what is K_c' for the reaction 4 A⇌ 2B?

Accepted Answer

The answer of If K_c is the equilibrium constant for...

Question 8

The oxidation of sulfur dioxide by oxygen to sulfur trioxide has been implicated as an important step in the formation of acid rain: 2 SO₂(g)+ O₂(g)⇌ 2 SO₃(g).If the equilibrium partial pressures of SO₂,O₂,and SO₃ are 0.564 atm,0.102 atm,and 0.333 atm respectively at 1000 K,what is K_p at that temperature?

Accepted Answer

The equilibrium constant $K_p$ for the reaction is calculated using the formula $K_p = \frac{(P_{SO_3})^2}{(P_{SO_2})^2(P_{O_2})}$, where $P$ represents the partial pressures of the gases. Substituting the given values, $K_p = \frac{(0.333)^2}{(0.564)^2(0.102)} = 3.42$.

Question 9

Which one of the following statements does not describe the equilibrium state?

Accepted Answer

The equilibrium state does not necessarily mean that the concentration of the reactants and products have to be equal. In some cases, the concentration of one species may be much higher or lower than the other. However, the rate of the forward reaction and the rate of the reverse reaction must be equal at equilibrium.

Question 10

K_p = 1.5 × 10³ at 400°C for the reaction 2 NH₃(g)⇌ N₂(g)+ 3 H₂(g).What is the value of K_p for the reaction: 2 N₂(g)+ 6 H₂(g)⇌ 4 NH₃(g)?

Accepted Answer

The equilibrium constant for the reverse reaction is the reciprocal of the original, and for the reaction multiplied by a factor (in this case 2), the equilibrium constant is raised to the power of that factor. Given $K_p = 1.5 \times 10^{13}$ for the forward reaction, the reverse reaction's $K_p$ would be $1/(1.5 \times 10^{13})$, and when the reaction is doubled, $K_p$ becomes $(1/(1.5 \times 10^{13}))^2 = 4.4 \times 10^{-27}$.

Question 11

The equilibrium equation is also known as the law of

Accepted Answer

The equilibrium equation is also known as the law of mass action, which describes the relationship between the concentrations of reactants and products at equilibrium. It states that the product of the concentrations of the products raised to their stoichiometric coefficients divided by the product of the concentrations of the reactants raised to their stoichiometric coefficients is a constant for a given reaction at a given temperature.

Question 12

Which statement about the equilibrium constant is true? The value of K_c

Accepted Answer

The equilibrium constant, K_c, only changes as temperature changes. It remains constant with respect to changes in reactant and product concentrations. Therefore, choice A and B are incorrect. Choice D is also incorrect, as it implies that the equilibrium constant changes under all three conditions, which is not true.

Question 13

Write the equilibrium equation for the forward reaction: 2 CH₄(g)+ 3 O₂(g)⇌ 2 CO(g)+ 4 H₂O(g)

Accepted Answer

The equilibrium constant expression for this reaction is Kp = ([CO]^2[HS12O4]^4) / ([CH₄]^2[O12S1U1B3]^3). Option B matches this expression, while the other options do not.

Question 14

What is the equilibrium equation for the reaction: NH₄NO₃(s)⇌ N₂O(g)+ 2 H₂O(g)?

Accepted Answer

The answer of What is the equilibrium equation for the...

Question 15

If K_c = 7.04 × 10^-2 for the reaction: 2 HBr(g)⇌ H₂(g)+ Br₂(g),what is the value of K_c for the reaction: ?

Accepted Answer

The answer of If K_c = 7.04 × 10^-2 for...

Question 16

For the reaction: N₂(g)+ 2 O₂(g)⇌ 2 NO₂(g),K_c = 8.3 × 10^-10 at 25°C.What is the concentration of N₂ gas at equilibrium when the concentration of NO₂ is twice the concentration of O₂ gas?

Accepted Answer

Let's assume that the initial concentration of OS1U1B12S1U1B0 is x M. Then, the initial concentration of NOS1U1B12S1U1B0 is 2x M. The initial concentration of NS1U1B12S1U1B0 is 0 M (since it is not given).

At equilibrium, let's assume that the concentration of NS1U1B12S1U1B0 is y M. Then, the concentration of OS1U1B12S1U1B0 becomes (x - 2y) M and the concentration of NOS1U1B12S1U1B0 becomes (2x + y) M.

We can now use the equilibrium constant expression to find the concentration of NS1U1B12S1U1B0:

KS1U1B1cS1U1B0 = [NOS1U1B12S1U1B0]2 / ([NS1U1B12S1U1B0][OS1U1B12S1U1B0]2)
8.3 × 10S1U1P1-10S1S1P0 = (2x + y)2 / (y(x - 2y)2)

Simplifying this expression and rearranging, we get:

y3 - 4xy2 + 4x2y - 8.3 × 10S1U1P1-10S1S1P0yx2 = 0

This is a cubic equation in y, and we can solve it using the cubic formula or numerical methods. However, in this case, the answer choices are all in some multiple of 10S1U1P19S1S1P0 M, which suggests that the problem can be solved using estimates.

Since the equilibrium constant is very small (10S1U1P1-10S1S1P0), we can assume that the concentration of NS1U1B12S1U1B0 is very small compared to the concentrations of OS1U1B12S1U1B0 and NOS1U1B12S1U1B0. This means that we can approximate:

y << x
y << 2x

With these approximations, we can simplify the cubic equation to:

- 8.3 × 10S1U1P1-10S1S1P0x2 ≈ 0

Solving for x, we get:

x ≈ √(8.3 × 10S1U1P1-10S1S1P0) ≈ 9.12 × 10S1U1P-6S1S1P0 M

Using this value of x, we can find y:

KS1U1B1cS1U1B0 = (2x + y)2 / (y(x - 2y)2)
8.3 × 10S1U1P1-10S1S1P0 ≈ (2x)2 / (y(x - 2y)2)
y(x - 2y)2 ≈ (2x)2 / 8.3 × 10S1U1P1-10S1S1P0
y(x2 - 4xy + 4y2) ≈ (2x)2 / 8.3 × 10S1U1P1-10S1S1P0
y(16x2) ≈ (2x)2 / 8.3 × 10S1U1P1-10S1S1P0
y ≈ (2x)2 / (16x2 × 8.3 × 10S1U1P1-10S1S1P0)
y ≈ 4.8 × 10S1U1P19S1S1P0 M

Therefore, the answer is D: 4.8 × 10S1U1P19S1S1P0 M.

Question 17

Given the reaction: 2 HI ⇌ H₂ + I₂.If K_c^' for the reverse reaction is 1.85 × 10^-2 at 425°C,what is K_c for the forward reaction at the same temperature?

Accepted Answer

The equilibrium constant for the forward reaction ($K_c$) is the reciprocal of the equilibrium constant for the reverse reaction. Given $K_c$ for the reverse reaction is $1.85 \times 10^{-2}$, for the forward reaction it is $1 / (1.85 \times 10^{-2}) = 54.1$.

Question 18

Which one of the following statements about the equilibrium constant,K_p,is false?

Accepted Answer

The statement that is false is D) Total pressures are used in the equilibrium equation in place of molar concentrations. The equilibrium constant (K) is calculated using the concentrations of the reactants and products at equilibrium, not their total pressures. However, the equilibrium constant (K) for a gaseous reaction can also be expressed in terms of partial pressures, using the relationship Kp = Kc(RT)^(Δn), where Δn is the difference between the sum of the stoichiometric coefficients of the gaseous products and the sum of the stoichiometric coefficients of the gaseous reactants. The units of K are dependent on the units of concentration or partial pressure used.

Question 19

Nitric oxide reacts with oxygen to form nitrogen dioxide: 2 NO(g)+ O₂(g)⇌ 2 NO₂(g) What is K_c'for the reverse reaction if the equilibrium concentration of NO is 0.300 M,O₂ is 0.200 M,and NO₂ is 0.530 M at 25°C?

Accepted Answer

The equilibrium constant expression for the given reaction is: Kc = [NO₂]^2 / ([NO]^2 * [O₂]) Substituting the given equilibrium concentrations: Kc = (0.530 M)^2 / ((0.300 M)^2 * (0.200 M)) = 0.0641 Since the given equilibrium is for the forward reaction, the equilibrium constant for the reverse reaction is the reciprocal of Kc: Kc' = 1/Kc = 1/0.0641 = 15.6 Therefore, the answer is B.

Question 20

K_p is related to K_c by the equation K_p = K_c (RT)ⁿ.What is the value of n for the reaction below? NH₄NO₃(s)⇌ N₂O(g)+ 2 H₂O(g)

Accepted Answer

Since K_p is related to K_c by the equation K_p = K_c (RT)ⁿ, we can compare the coefficients of the species that appear in both compounds. In the given equation, we can see that the coefficient of H₂O(g) changes from 1 to 2, while the coefficients of the other species remain the same. Therefore, n = 2 - 1 = +1. This means that the reaction shifts to the right with an increase in temperature, leading to an increase in the concentration of products (N₂O(g) and H₂O(g)). So, the best choice is option D.

Quiz 14: Chemical Equilibrium

If K_c is the equilibrium constant for a forward reaction what is K_c' for the reverse reaction?

Write the equilibrium equation for the reverse reaction: 2 CH₄(g) + 3 O₂(g) ⇌ 2 CO(g) + 4 H₂O(g)

Which of the following statements is false regarding the equilibrium constant,K_c?

A mixture of carbon monoxide,hydrogen,and methanol is at equilibrium.The balanced chemical equation is: CO(g) + 2 H₂(g) ⇌ CH₃OH(g) .At 250°C,the mixture contains 0.0960 M CO,0.191 M H₂,and 0.150 M CH₃OH.What is the value for K_c?

What is true about the relationship of K_p and K_cfor the reaction: 2 CH₄(g) + 3 O₂(g) ⇌ 2 CO(g) + 4 H₂O(g) ?

Which statement about the equilibrium constant is true? The value of K_c

If K_c is the equilibrium constant for a forward reaction,2 A⇌ B,what is K_c' for the reaction 4 A⇌ 2B?

Which one of the following statements does not describe the equilibrium state?

K_p = 1.5 × 10³ at 400°C for the reaction 2 NH₃(g) ⇌ N₂(g) + 3 H₂(g) .What is the value of K_p for the reaction: 2 N₂(g) + 6 H₂(g) ⇌ 4 NH₃(g) ?

The equilibrium equation is also known as the law of

Which statement about the equilibrium constant is true? The value of K_c

Write the equilibrium equation for the forward reaction: 2 CH₄(g) + 3 O₂(g) ⇌ 2 CO(g) + 4 H₂O(g)

What is the equilibrium equation for the reaction: NH₄NO₃(s) ⇌ N₂O(g) + 2 H₂O(g) ?

If K_c = 7.04 × 10^-2 for the reaction: 2 HBr(g) ⇌ H₂(g) + Br₂(g) ,what is the value of K_c for the reaction: ?

For the reaction: N₂(g) + 2 O₂(g) ⇌ 2 NO₂(g) ,K_c = 8.3 × 10^-10 at 25°C.What is the concentration of N₂ gas at equilibrium when the concentration of NO₂ is twice the concentration of O₂ gas?

Given the reaction: 2 HI ⇌ H₂ + I₂.If K_c^' for the reverse reaction is 1.85 × 10^-2 at 425°C,what is K_c for the forward reaction at the same temperature?

Which one of the following statements about the equilibrium constant,K_p,is false?

Nitric oxide reacts with oxygen to form nitrogen dioxide: 2 NO(g) + O₂(g) ⇌ 2 NO₂(g) What is K_c'for the reverse reaction if the equilibrium concentration of NO is 0.300 M,O₂ is 0.200 M,and NO₂ is 0.530 M at 25°C?

K_p is related to K_c by the equation K_p = K_c (RT) ⁿ.What is the value of n for the reaction below? NH₄NO₃(s) ⇌ N₂O(g) + 2 H₂O(g)

Quiz 14: Chemical Equilibrium

If Kc is the equilibrium constant for a forward reaction what is Kc' for the reverse reaction?

Write the equilibrium equation for the reverse reaction: 2 CH4(g) + 3 O2(g) ⇌ 2 CO(g) + 4 H2O(g)

Which of the following statements is false regarding the equilibrium constant,Kc?

A mixture of carbon monoxide,hydrogen,and methanol is at equilibrium.The balanced chemical equation is: CO(g) + 2 H2(g) ⇌ CH3OH(g) .At 250°C,the mixture contains 0.0960 M CO,0.191 M H2,and 0.150 M CH3OH.What is the value for Kc?

What is true about the relationship of Kp and Kc for the reaction: 2 CH4(g) + 3 O2(g) ⇌ 2 CO(g) + 4 H2O(g) ?

Which statement about the equilibrium constant is true? The value of Kc

If Kc is the equilibrium constant for a forward reaction,2 A⇌ B,what is Kc' for the reaction 4 A⇌ 2B?

Which one of the following statements does not describe the equilibrium state?

Kp = 1.5 × 103 at 400°C for the reaction 2 NH3(g) ⇌ N2(g) + 3 H2(g) .What is the value of Kp for the reaction: 2 N2(g) + 6 H2(g) ⇌ 4 NH3(g) ?

The equilibrium equation is also known as the law of

Which statement about the equilibrium constant is true? The value of Kc

Write the equilibrium equation for the forward reaction: 2 CH4(g) + 3 O2(g) ⇌ 2 CO(g) + 4 H2O(g)

What is the equilibrium equation for the reaction: NH4NO3(s) ⇌ N2O(g) + 2 H2O(g) ?

If Kc = 7.04 × 10-2 for the reaction: 2 HBr(g) ⇌ H2(g) + Br2(g) ,what is the value of Kc for the reaction: ?

For the reaction: N2(g) + 2 O2(g) ⇌ 2 NO2(g) ,Kc = 8.3 × 10-10 at 25°C.What is the concentration of N2 gas at equilibrium when the concentration of NO2 is twice the concentration of O2 gas?

Given the reaction: 2 HI ⇌ H2 + I2.If Kc' for the reverse reaction is 1.85 × 10-2 at 425°C,what is Kc for the forward reaction at the same temperature?

Which one of the following statements about the equilibrium constant,Kp,is false?

Nitric oxide reacts with oxygen to form nitrogen dioxide: 2 NO(g) + O2(g) ⇌ 2 NO2(g) What is Kc' for the reverse reaction if the equilibrium concentration of NO is 0.300 M,O2 is 0.200 M,and NO2 is 0.530 M at 25°C?

Kp is related to Kc by the equation Kp = Kc (RT) n.What is the value of n for the reaction below? NH4NO3(s) ⇌ N2O(g) + 2 H2O(g)

If K_c is the equilibrium constant for a forward reaction what is K_c' for the reverse reaction?

Write the equilibrium equation for the reverse reaction: 2 CH₄(g) + 3 O₂(g) ⇌ 2 CO(g) + 4 H₂O(g)

Which of the following statements is false regarding the equilibrium constant,K_c?

A mixture of carbon monoxide,hydrogen,and methanol is at equilibrium.The balanced chemical equation is: CO(g) + 2 H₂(g) ⇌ CH₃OH(g) .At 250°C,the mixture contains 0.0960 M CO,0.191 M H₂,and 0.150 M CH₃OH.What is the value for K_c?

What is true about the relationship of K_p and K_cfor the reaction: 2 CH₄(g) + 3 O₂(g) ⇌ 2 CO(g) + 4 H₂O(g) ?

Which statement about the equilibrium constant is true? The value of K_c

If K_c is the equilibrium constant for a forward reaction,2 A⇌ B,what is K_c' for the reaction 4 A⇌ 2B?

K_p = 1.5 × 10³ at 400°C for the reaction 2 NH₃(g) ⇌ N₂(g) + 3 H₂(g) .What is the value of K_p for the reaction: 2 N₂(g) + 6 H₂(g) ⇌ 4 NH₃(g) ?

Which statement about the equilibrium constant is true? The value of K_c

Write the equilibrium equation for the forward reaction: 2 CH₄(g) + 3 O₂(g) ⇌ 2 CO(g) + 4 H₂O(g)

What is the equilibrium equation for the reaction: NH₄NO₃(s) ⇌ N₂O(g) + 2 H₂O(g) ?

If K_c = 7.04 × 10^-2 for the reaction: 2 HBr(g) ⇌ H₂(g) + Br₂(g) ,what is the value of K_c for the reaction: ?

For the reaction: N₂(g) + 2 O₂(g) ⇌ 2 NO₂(g) ,K_c = 8.3 × 10^-10 at 25°C.What is the concentration of N₂ gas at equilibrium when the concentration of NO₂ is twice the concentration of O₂ gas?

Given the reaction: 2 HI ⇌ H₂ + I₂.If K_c^' for the reverse reaction is 1.85 × 10^-2 at 425°C,what is K_c for the forward reaction at the same temperature?

Which one of the following statements about the equilibrium constant,K_p,is false?

Nitric oxide reacts with oxygen to form nitrogen dioxide: 2 NO(g) + O₂(g) ⇌ 2 NO₂(g) What is K_c'for the reverse reaction if the equilibrium concentration of NO is 0.300 M,O₂ is 0.200 M,and NO₂ is 0.530 M at 25°C?

K_p is related to K_c by the equation K_p = K_c (RT) ⁿ.What is the value of n for the reaction below? NH₄NO₃(s) ⇌ N₂O(g) + 2 H₂O(g)