Week 3 - review of equilibrium DP2 - Anita Martin | Library

Instructions

For all answers- an explanation can be found on the lesson powerpoint

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How did you do with the checking comprehension question?

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How did you do with the checking comprehension question?

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Which change increases the concentration of ammonium ions in the reaction below?
NH3 (g) + H2O (l) ⇌ NH4+ (aq) + OH– (aq) ΔH > 0
A.Decreasing the pressure
B.Decreasing the temperature
C.Adding an acid
D.Removing water

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Which combination of standard change of Gibbs free energy (ΔG⦵) and equilibrium constant (K) is most typical for a reaction that goes to completion?

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0.80 mol of propanoic acid and 0.80 mol of methanol are mixed in a 1.0 dm3reaction vessel. These reactants reach an equilibrium through an esterification reaction according to the following equation:
CH3OH (l) + CH3CH2COOH (l) ⇌ CH3CH2COOCH3 (l) + H2O (l)
At equilibrium the amount of each product present is 0.37 mol. Determine the value of the equilibrium constant, Kc, to two decimal places.

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The equilibrium constant expression, Kc, for a reaction is:
Kc= ([B][C])/( [A]2)
At a certain temperature the equilibrium values of [A], [B] and [C] are all 0.200 mol dm-3. What will happen to the value of Kc if these concentrations are doubled at constant temperature?
A.the value of Kc doubles
B.the value of Kc remains constant
C.the value of Kc is halved
D.the value of Kc increases by a factor of 4

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Write the expression for the equilibrium constant, Kc, for this reaction.

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Calculate the value of Kc at each of the two temperatures given.

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Is the forward reaction endothermic or exothermic? (Explain your answer)

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The acid-catalysedhydrolysis of ethyl ethanoate can be achieved by mixing the ester with dilute hydrochloric acid.
H+
CH3COOC2H5(l) + H2O(l) ⇋ CH3COOH(l) + C2H5OH(l)
If 1.00 mole of ethyl ethanoate is mixed with 1.00 mole of water and the reaction is allowed to reach equilibrium at a particular temperature, then 0.30 moles of ethanoic acid is found in the equilibrium mixture.
Calculate the value of Kc at this temperature.

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An organic compound X exists in equilibrium with its isomer, Y, in the liquid state at a particular temperature.
X(l) ⇋ Y(l)
Calculate how many moles of Y are formed at equilibrium if 1 mole of X is allowed to reach equilibrium at this temperature, if Kc has a value of 0.020.

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The esterification reaction between ethanol and ethanoic acid has a free energy change (ΔG1) of –4.38 kJmol–1. Calculate the value of Kc for this reaction at 25°C (298K). (R = 8.31 JK–1mol–1)

Week 3 - review of equilibrium DP2

Week 3 - review of equilibrium DP2

How did you do with the checking comprehension question?

How did you do with the checking comprehension question?

Which change increases the concentration of ammonium ions in the reaction below?NH3 (g) + H2O (l) ⇌ NH4+ (aq) + OH– (aq) ΔH > 0A.Decreasing the pressureB.Decreasing the temperatureC.Adding an acidD.Removing water

Which combination of standard change of Gibbs free energy (ΔG⦵) and equilibrium constant (K) is most typical for a reaction that goes to completion?

Write the expression for the equilibrium constant, Kc, for this reaction.

Calculate the value of Kc at each of the two temperatures given.

Is the forward reaction endothermic or exothermic? (Explain your answer)

An organic compound X exists in equilibrium with its isomer, Y, in the liquid state at a particular temperature.X(l) ⇋ Y(l)Calculate how many moles of Y are formed at equilibrium if 1 mole of X is allowed to reach equilibrium at this temperature, if Kc has a value of 0.020.

The esterification reaction between ethanol and ethanoic acid has a free energy change (ΔG1) of –4.38 kJmol–1. Calculate the value of Kc for this reaction at 25°C (298K). (R = 8.31 JK–1mol–1)

How did you do with the checking comprehension question?

How did you do with the checking comprehension question?

Which change increases the concentration of ammonium ions in the reaction below?NH3 (g) + H2O (l) ⇌ NH4+ (aq) + OH– (aq) ΔH > 0A.Decreasing the pressureB.Decreasing the temperatureC.Adding an acidD.Removing water

Which combination of standard change of Gibbs free energy (ΔG⦵) and equilibrium constant (K) is most typical for a reaction that goes to completion?

Write the expression for the equilibrium constant, Kc, for this reaction.

Calculate the value of Kc at each of the two temperatures given.

Is the forward reaction endothermic or exothermic? (Explain your answer)

An organic compound X exists in equilibrium with its isomer, Y, in the liquid state at a particular temperature.X(l) ⇋ Y(l)Calculate how many moles of Y are formed at equilibrium if 1 mole of X is allowed to reach equilibrium at this temperature, if Kc has a value of 0.020.

The esterification reaction between ethanol and ethanoic acid has a free energy change (ΔG1) of –4.38 kJmol–1. Calculate the value of Kc for this reaction at 25°C (298K). (R = 8.31 JK–1mol–1)

Which change increases the concentration of ammonium ions in the reaction below?
NH3 (g) + H2O (l) ⇌ NH4+ (aq) + OH– (aq) ΔH > 0
A.Decreasing the pressure
B.Decreasing the temperature
C.Adding an acid
D.Removing water

An organic compound X exists in equilibrium with its isomer, Y, in the liquid state at a particular temperature.
X(l) ⇋ Y(l)
Calculate how many moles of Y are formed at equilibrium if 1 mole of X is allowed to reach equilibrium at this temperature, if Kc has a value of 0.020.

Which change increases the concentration of ammonium ions in the reaction below?
NH3 (g) + H2O (l) ⇌ NH4+ (aq) + OH– (aq) ΔH > 0
A.Decreasing the pressure
B.Decreasing the temperature
C.Adding an acid
D.Removing water

An organic compound X exists in equilibrium with its isomer, Y, in the liquid state at a particular temperature.
X(l) ⇋ Y(l)
Calculate how many moles of Y are formed at equilibrium if 1 mole of X is allowed to reach equilibrium at this temperature, if Kc has a value of 0.020.