Question 1

For the reaction: PCl₃(g) + Cl₂(g) ⇌ PCl₅(g) at 70.5°C, Kp = 1.05. If one starts with 1.80 atm pressure of PCl₃(g), 1.72 atm pressure of Cl₂(g), and no PCl₅(g), what is the partial pressure of PCl₅(g) at equilibrium?

Accepted Answer

To find the partial pressure of PCl5 at equilibrium, use the expression for Kp: Kp = (P_PCl5) / (P_PCl3 * P_Cl2). Let x be the change in pressure at equilibrium. Then, P_PCl5 = x, P_PCl3 = 1.80 - x, and P_Cl2 = 1.72 - x. Substitute these into the Kp expression and solve for x, which gives approximately 0.856 atm.

Question 2

Write the equilibrium constant expression for the following reaction: 2 KI(aq) + H₂O₂(aq) ⇌ 2 KOH(aq) + I₂(aq)

Accepted Answer

The answer of Write the equilibrium constant expression for the...

Question 3

For the reaction: 2 Cl₂(g) + 2 H₂O(g) ⇌ 4 HCl(g) + O₂(g), Kp = 6.4 × 10^-6 at 500 K. If a fixed volume is filled with initial concentrations of these gases at 227°C such that [Cl₂] = 0.5 M, [H₂O] = 0.40 M, [HCl] = 0.5 M, and [O₂] = 0.015 M, in which direction will the reaction proceed?

Accepted Answer

Comparing the initial concentrations with the equilibrium constant, it is evident that the reaction quotient (Qp) is greater than Kp. Therefore, the reaction will shift towards the reactants to reach equilibrium, meaning it will proceed to the left.

Question 4

Find Kp for the following reaction at 25.0°C. SbCl₅(g) ⇌ SbCl₃(g) + Cl₂(g) Kc = 2.51 × 10^-2

Accepted Answer

Kp = Kc(RT)^Δn = (2.51 × 10^-2)(0.0821)(298)^1 = 0.614

Question 5

For a reaction, the reaction quotient, Qc > Kc, the reaction ________.

Accepted Answer

The reaction quotient (Qc) is the ratio of the concentrations of products to reactants at any given point in the reaction. If Qc is greater than the equilibrium constant (Kc), it means that the concentration of products is too high and the concentration of reactants is too low for equilibrium. To reach equilibrium, the reaction will shift to the left (towards the reactants) to decrease the concentration of products and increase the concentration of reactants until Qc equals Kc. Therefore, the correct answer is D, the reaction shifts to the left.

Question 6

For the reaction 2 NO(g)⇌ N₂O₄(g) Kp equals ________.

Accepted Answer

Kp = Kc(RT)^Δn, where Δn is the difference in the number of moles of gaseous products and reactants. Since Δn = (1-2) = -1 for this reaction, Kp = Kc/RT.

Question 7

For the reaction 2 A(g) ⇌ B(g) + C(g), Kc = 1.25 at 300 K. If a 1.00 L mixture contains 0.619 mol A, 0.693 mol B, and 0.689 mol C at 300 K, will the mixture be in equilibrium? If not, in what direction will a net reaction occur?

Accepted Answer

The answer of For the reaction 2 A(g) ⇌ B(g)...

Question 8

At a certain temperature, Kc = 0.0500 and △H = +39.6 kJ for the reaction below. 2MgCl₂(s) + O₂(g) ⇌ 2MgO(s) + 2Cl₂(g) Calculate Kc for the reaction MgO(s) + Cl₂(g) ⇌ MgCl₂(s) + O₂(g) And indicate whether the value will be larger or smaller at a lower temperature.

Accepted Answer

The answer of At a certain temperature, Kc = 0.0500...

Question 9

What is the relationship between Kp and Kc for the reaction below? 4NH₃(g) + 7O₂(g) ⇌ 2N₂O₄(g) + 6H₂O(g)

Accepted Answer

The relationship between Kp and Kc is given by the equation Kp = Kc(RT)^(Δn), where Δn is the change in moles of gas. Here, Δn = (2 + 6) - (4 + 7) = -3, so Kp = Kc(RT)^-3.

Question 10

Write the equilibrium constant expression for the following reaction: 6 CO₂(g) + 6 H₂O(l) ⇌ C₆H₁₂O₆(s) + 6 O₂(g)

Accepted Answer

The answer of Write the equilibrium constant expression for the...

Question 11

Write the equilibrium expression Kc for the reaction: sodium sulfite(aq) + chloric acid (aq) ⇌ sodium chlorite(aq) + sulfur dioxide(g) + water(l).

Accepted Answer

The answer of Write the equilibrium expression Kc for the...

Question 12

For the reaction: 3 Fe(s) + 4 H₂O(g) ⇌ Fe₃O₄(s) + 4 H₂(g) Write the expression for Kp.

Accepted Answer

The answer of For the reaction: 3 Fe(s) + 4...

Question 13

For the reaction: 2 SO₂(g) + O₂(g) ⇌ 2 SO₃(g), Kc = 6.9 × 10²⁴ at 25°C. If a reaction vessel is filled with these gases, such that [SO₂] = 6.0 M, [O₂] = 6.0 M and [SO₃] = 6.0 M, in which direction will the reaction proceed?

Accepted Answer

The reaction quotient, Qc, can be found by plugging in the given concentrations into the expression for Kc. Qc = [SO₃]2 /[SO₂]2 [O₂] Qc = (6.0 M)2 / (6.0 M)2 (6.0 M) = 1.0 Since Qc is smaller than Kc, the reaction will proceed to the right to reach equilibrium and increase the concentration of SO₃. Therefore, the answer is A.

Question 14

Two moles of NH₃ are initially present for the reaction: 2 NH₃(g) ⇌ N₂(g) + 3 H₂(g) At equilibrium there is 1.00 mol NH₃. How many moles of H₂ are present at equilibrium?

Accepted Answer

According to the balanced chemical equation, for every 2 moles of NH₃ that react, 3 moles of H₂ are produced. At equilibrium, there is 1 mole of NH₃ present, which means that 3/2 moles of H₂ must be present to satisfy the stoichiometry of the reaction. Therefore, the answer is 1.50 moles or choice C.

Question 15

Given the following reactions, 2PCl₃(g) ⇌ 2P(g) + 3Cl₂(g) Kc = 0.0667 PCl₃(g) + Cl₂(g) ⇌ PCl₅(g) Kc = 4.0 Calculate Kc for the reaction below. 2P(g) + 5Cl₂(g) ⇌ 2PCl₅(g)

Accepted Answer

To solve for Kc of the given reaction, we can combine the two given reactions and cancel out the intermediate species, Cl2(g) and P(g). 
First, we reverse the first equation: 
2P(g) + 3Cl2(g) ⇌ 2PCl3(g)
Taking the reciprocal of the equation gives: 
PCl3(g)/P2(g)Cl3(g) = 1/Kc1 = 15 
Next, we multiply the second equation by the appropriate factor to cancel out Cl2(g): 
2PCl3(g) + 2Cl2(g) ⇌ 2PCl5(g) 
Multiplying the first equation by 2 and adding it to the second equation, we get: 
2P2(g) + 6Cl2(g) ⇌ 2PCl5(g) 
Dividing by P2(g)Cl5(g) gives: 
PCl5(g)/P2(g)^2Cl5(g) = Kc2/Kc1 = 4/0.0667 = 60.006
Therefore, Kc for 2P(g) + 5Cl2(g) ⇌ 2PCl5(g) is: 
(PCl5(g))^2/(P2(g))^5(Cl2(g))^10 = Kc2 = (P2(g)^2(Cl5(g))^2)/(P2(g))^5(Cl2(g))^10 = 240.

Question 16

For the reaction: 3 Fe(s) + 4 H₂O(g) ⇌ Fe₃O₄(s) + 4 H₂(g) write the expression for Kc in terms of Kp.

Accepted Answer

The answer of For the reaction: 3 Fe(s) + 4...

Question 17

Write the equilibrium constant expression for the reaction: 3 Sn(s) + 4 HNO₃(aq) + H₂O(l) ⇌ 3 H₂SnO₃(s) + 4 NO(g)

Accepted Answer

The answer of Write the equilibrium constant expression for the...

Question 18

Consider the following hypothetical equilibrium reaction: A₂(g) + B₂(g) ⇌ 2AB(g) where Kc = The equilibrium constant for the reaction: 2 A₂(g) + 2 B₂(g) ⇔ 4 AB(g) is ________.

Accepted Answer

The answer of Consider the following hypothetical equilibrium reaction: A₂(g)...

Question 19

For the reaction: 3 Fe(s) + 4 H₂O(g) ⇌ Fe₃O₄(s) + 4 H₂(g) what is the effect of adding Fe(s)?

Accepted Answer

The answer of For the reaction: 3 Fe(s) + 4...

Question 20

In the reaction: 2 N₂O(g) + N₂H₄(g) ⇌ 3 N₂(g) + 2 H₂O(g), One starts with 0.10 mol N₂O and 0.25 mol N₂H₄ in a 10.0 L container. If there are 0.06 mol N₂O at equilibrium, how many moles of N₂ are present?

Accepted Answer

The answer of In the reaction: 2 N₂O(g) + N₂H₄(g)...

Quiz 15: Principles of Chemical Equilibrium

For the reaction: PCl₃(g) + Cl₂(g) ⇌ PCl₅(g) at 70.5°C, Kp = 1.05. If one starts with 1.80 atm pressure of PCl₃(g) , 1.72 atm pressure of Cl₂(g) , and no PCl₅(g) , what is the partial pressure of PCl₅(g) at equilibrium?

Write the equilibrium constant expression for the following reaction: 2 KI(aq) + H₂O₂(aq) ⇌ 2 KOH(aq) + I₂(aq)

Find Kp for the following reaction at 25.0°C. SbCl₅(g) ⇌ SbCl₃(g) + Cl₂(g) Kc = 2.51 × 10^-2

For a reaction, the reaction quotient, Qc > Kc, the reaction ________.

For the reaction 2 NO(g) ⇌ N₂O₄(g) Kp equals ________.

For the reaction 2 A(g) ⇌ B(g) + C(g) , Kc = 1.25 at 300 K. If a 1.00 L mixture contains 0.619 mol A, 0.693 mol B, and 0.689 mol C at 300 K, will the mixture be in equilibrium? If not, in what direction will a net reaction occur?

At a certain temperature, Kc = 0.0500 and △H = +39.6 kJ for the reaction below. 2MgCl₂(s) + O₂(g) ⇌ 2MgO(s) + 2Cl₂(g) Calculate Kc for the reaction MgO(s) + Cl₂(g) ⇌ MgCl₂(s) + O₂(g) And indicate whether the value will be larger or smaller at a lower temperature.

What is the relationship between Kp and Kc for the reaction below? 4NH₃(g) + 7O₂(g) ⇌ 2N₂O₄(g) + 6H₂O(g)

Write the equilibrium constant expression for the following reaction: 6 CO₂(g) + 6 H₂O(l) ⇌ C₆H₁₂O₆(s) + 6 O₂(g)

Write the equilibrium expression Kc for the reaction: sodium sulfite(aq) + chloric acid (aq) ⇌ sodium chlorite(aq) + sulfur dioxide(g) + water(l) .

For the reaction: 3 Fe(s) + 4 H₂O(g) ⇌ Fe₃O₄(s) + 4 H₂(g) Write the expression for Kp.

For the reaction: 2 SO₂(g) + O₂(g) ⇌ 2 SO₃(g) , Kc = 6.9 × 10²⁴ at 25°C. If a reaction vessel is filled with these gases, such that [SO₂] = 6.0 M, [O₂] = 6.0 M and [SO₃] = 6.0 M, in which direction will the reaction proceed?

Two moles of NH₃ are initially present for the reaction: 2 NH₃(g) ⇌ N₂(g) + 3 H₂(g) At equilibrium there is 1.00 mol NH₃. How many moles of H₂ are present at equilibrium?

Given the following reactions, 2PCl₃(g) ⇌ 2P(g) + 3Cl₂(g) Kc = 0.0667 PCl₃(g) + Cl₂(g) ⇌ PCl₅(g) Kc = 4.0 Calculate Kc for the reaction below. 2P(g) + 5Cl₂(g) ⇌ 2PCl₅(g)

For the reaction: 3 Fe(s) + 4 H₂O(g) ⇌ Fe₃O₄(s) + 4 H₂(g) write the expression for Kc in terms of Kp.

Write the equilibrium constant expression for the reaction: 3 Sn(s) + 4 HNO₃(aq) + H₂O(l) ⇌ 3 H₂SnO₃(s) + 4 NO(g)

Consider the following hypothetical equilibrium reaction: A₂(g) + B₂(g) ⇌ 2AB(g) where Kc = The equilibrium constant for the reaction: 2 A₂(g) + 2 B₂(g) ⇔ 4 AB(g) is ________.

For the reaction: 3 Fe(s) + 4 H₂O(g) ⇌ Fe₃O₄(s) + 4 H₂(g) what is the effect of adding Fe(s) ?

In the reaction: 2 N₂O(g) + N₂H₄(g) ⇌ 3 N₂(g) + 2 H₂O(g) , One starts with 0.10 mol N₂O and 0.25 mol N₂H₄ in a 10.0 L container. If there are 0.06 mol N₂O at equilibrium, how many moles of N₂ are present?

Quiz 15: Principles of Chemical Equilibrium

For the reaction: PCl3(g) + Cl2(g) ⇌ PCl5(g) at 70.5°C, Kp = 1.05. If one starts with 1.80 atm pressure of PCl3(g) , 1.72 atm pressure of Cl2(g) , and no PCl5(g) , what is the partial pressure of PCl5(g) at equilibrium?

Write the equilibrium constant expression for the following reaction: 2 KI(aq) + H2O2(aq) ⇌ 2 KOH(aq) + I2(aq)

For the reaction: 2 Cl2(g) + 2 H2O(g) ⇌ 4 HCl(g) + O2(g) , Kp = 6.4 × 10-6 at 500 K. If a fixed volume is filled with initial concentrations of these gases at 227°C such that [Cl2] = 0.5 M, [H2O] = 0.40 M, [HCl] = 0.5 M, and [O2] = 0.015 M, in which direction will the reaction proceed?

Find Kp for the following reaction at 25.0°C. SbCl5(g) ⇌ SbCl3(g) + Cl2(g) Kc = 2.51 × 10-2

For a reaction, the reaction quotient, Qc > Kc, the reaction ________.

For the reaction 2 NO(g) ⇌ N2O4(g) Kp equals ________.

For the reaction 2 A(g) ⇌ B(g) + C(g) , Kc = 1.25 at 300 K. If a 1.00 L mixture contains 0.619 mol A, 0.693 mol B, and 0.689 mol C at 300 K, will the mixture be in equilibrium? If not, in what direction will a net reaction occur?

At a certain temperature, Kc = 0.0500 and △H = +39.6 kJ for the reaction below. 2MgCl2(s) + O2(g) ⇌ 2MgO(s) + 2Cl2(g) Calculate Kc for the reaction MgO(s) + Cl2(g) ⇌ MgCl2(s) + O2(g) And indicate whether the value will be larger or smaller at a lower temperature.

What is the relationship between Kp and Kc for the reaction below? 4NH3(g) + 7O2(g) ⇌ 2N2O4(g) + 6H2O(g)

Write the equilibrium constant expression for the following reaction: 6 CO2(g) + 6 H2O(l) ⇌ C6H12O6(s) + 6 O2(g)

Write the equilibrium expression Kc for the reaction: sodium sulfite(aq) + chloric acid (aq) ⇌ sodium chlorite(aq) + sulfur dioxide(g) + water(l) .

For the reaction: 3 Fe(s) + 4 H2O(g) ⇌ Fe3O4(s) + 4 H2(g) Write the expression for Kp.

For the reaction: 2 SO2(g) + O2(g) ⇌ 2 SO3(g) , Kc = 6.9 × 1024 at 25°C. If a reaction vessel is filled with these gases, such that [SO2] = 6.0 M, [O2] = 6.0 M and [SO3] = 6.0 M, in which direction will the reaction proceed?

Two moles of NH3 are initially present for the reaction: 2 NH3(g) ⇌ N2(g) + 3 H2(g) At equilibrium there is 1.00 mol NH3. How many moles of H2 are present at equilibrium?

Given the following reactions, 2PCl3(g) ⇌ 2P(g) + 3Cl2(g) Kc = 0.0667 PCl3(g) + Cl2(g) ⇌ PCl5(g) Kc = 4.0 Calculate Kc for the reaction below. 2P(g) + 5Cl2(g) ⇌ 2PCl5(g)

For the reaction: 3 Fe(s) + 4 H2O(g) ⇌ Fe3O4(s) + 4 H2(g) write the expression for Kc in terms of Kp.

Write the equilibrium constant expression for the reaction: 3 Sn(s) + 4 HNO3(aq) + H2O(l) ⇌ 3 H2SnO3(s) + 4 NO(g)

Consider the following hypothetical equilibrium reaction: A2(g) + B2(g) ⇌ 2AB(g) where Kc = The equilibrium constant for the reaction: 2 A2(g) + 2 B2(g) ⇔ 4 AB(g) is ________.

For the reaction: 3 Fe(s) + 4 H2O(g) ⇌ Fe3O4(s) + 4 H2(g) what is the effect of adding Fe(s) ?

In the reaction: 2 N2O(g) + N2H4(g) ⇌ 3 N2(g) + 2 H2O(g) , One starts with 0.10 mol N2O and 0.25 mol N2H4 in a 10.0 L container. If there are 0.06 mol N2O at equilibrium, how many moles of N2 are present?

For the reaction: PCl₃(g) + Cl₂(g) ⇌ PCl₅(g) at 70.5°C, Kp = 1.05. If one starts with 1.80 atm pressure of PCl₃(g) , 1.72 atm pressure of Cl₂(g) , and no PCl₅(g) , what is the partial pressure of PCl₅(g) at equilibrium?

Write the equilibrium constant expression for the following reaction: 2 KI(aq) + H₂O₂(aq) ⇌ 2 KOH(aq) + I₂(aq)

Find Kp for the following reaction at 25.0°C. SbCl₅(g) ⇌ SbCl₃(g) + Cl₂(g) Kc = 2.51 × 10^-2

For the reaction 2 NO(g) ⇌ N₂O₄(g) Kp equals ________.

At a certain temperature, Kc = 0.0500 and △H = +39.6 kJ for the reaction below. 2MgCl₂(s) + O₂(g) ⇌ 2MgO(s) + 2Cl₂(g) Calculate Kc for the reaction MgO(s) + Cl₂(g) ⇌ MgCl₂(s) + O₂(g) And indicate whether the value will be larger or smaller at a lower temperature.

What is the relationship between Kp and Kc for the reaction below? 4NH₃(g) + 7O₂(g) ⇌ 2N₂O₄(g) + 6H₂O(g)

Write the equilibrium constant expression for the following reaction: 6 CO₂(g) + 6 H₂O(l) ⇌ C₆H₁₂O₆(s) + 6 O₂(g)

For the reaction: 3 Fe(s) + 4 H₂O(g) ⇌ Fe₃O₄(s) + 4 H₂(g) Write the expression for Kp.

For the reaction: 2 SO₂(g) + O₂(g) ⇌ 2 SO₃(g) , Kc = 6.9 × 10²⁴ at 25°C. If a reaction vessel is filled with these gases, such that [SO₂] = 6.0 M, [O₂] = 6.0 M and [SO₃] = 6.0 M, in which direction will the reaction proceed?

Two moles of NH₃ are initially present for the reaction: 2 NH₃(g) ⇌ N₂(g) + 3 H₂(g) At equilibrium there is 1.00 mol NH₃. How many moles of H₂ are present at equilibrium?

Given the following reactions, 2PCl₃(g) ⇌ 2P(g) + 3Cl₂(g) Kc = 0.0667 PCl₃(g) + Cl₂(g) ⇌ PCl₅(g) Kc = 4.0 Calculate Kc for the reaction below. 2P(g) + 5Cl₂(g) ⇌ 2PCl₅(g)

For the reaction: 3 Fe(s) + 4 H₂O(g) ⇌ Fe₃O₄(s) + 4 H₂(g) write the expression for Kc in terms of Kp.

Write the equilibrium constant expression for the reaction: 3 Sn(s) + 4 HNO₃(aq) + H₂O(l) ⇌ 3 H₂SnO₃(s) + 4 NO(g)

Consider the following hypothetical equilibrium reaction: A₂(g) + B₂(g) ⇌ 2AB(g) where Kc = The equilibrium constant for the reaction: 2 A₂(g) + 2 B₂(g) ⇔ 4 AB(g) is ________.

For the reaction: 3 Fe(s) + 4 H₂O(g) ⇌ Fe₃O₄(s) + 4 H₂(g) what is the effect of adding Fe(s) ?

In the reaction: 2 N₂O(g) + N₂H₄(g) ⇌ 3 N₂(g) + 2 H₂O(g) , One starts with 0.10 mol N₂O and 0.25 mol N₂H₄ in a 10.0 L container. If there are 0.06 mol N₂O at equilibrium, how many moles of N₂ are present?