Calculate the standard enthalpy change for this reaction using the following data.

Calculate the standard entropy change for this reaction using the following data.

The standard free energy change, Δ_G_θ, for the above reaction is –103 kJ mol–1 at 298 K.

Suggest why Δ_G_θ has a large negative value considering the sign of Δ_H_θ in part (a).

Predict the electron domain and molecular geometries around the oxygen atom of molecule A using VSEPR

State the type of hybridization shown by the central carbon atom in molecule B.

State the number of sigma (σ) and pi (π) bonds around the central carbon atom in molecule B.

The IR spectrum of one of the compounds is shown:

COBLENTZ SOCIETY. Collection © 2018 copyright by the U.S. Secretary of Commerce on behalf of the United States of America. All rights reserved.

Deduce, giving a reason, the compound producing this spectrum.

Compound A and B are isomers. Draw two other structural isomers with the formula C3H6O.

The equilibrium constant, Kc, for the conversion of A to B is 1.0×108 in water at 298 K.

Deduce, giving a reason, which compound, A or B, is present in greater concentration when equilibrium is reached.

f(i).

Calculate the standard Gibbs free energy change, ∆G⦵, in kJ mol–1, for the reaction (A to B) at 298 K. Use sections 1 and 2 of the data booklet.

f(ii).

Propanone can be synthesized in two steps from propene.Suggest the synthetic route including all the necessary reactants and steps.

g(i).

Propanone can be synthesized in two steps from propene.

Suggest why propanal is a minor product obtained from the synthetic route in (g)(i).

g(ii).

State the electron configuration of the Cu+ ion.

a(i).

Copper(II) chloride is used as a catalyst in the production of chlorine from hydrogen chloride.

4HCl (g) + O2 (g) → 2Cl2 (g) + 2H2O (g)

Calculate the standard enthalpy change, Δ_H_θ, in kJ, for this reaction, using section 12 of the data booklet.

a(ii).

The diagram shows the Maxwell–Boltzmann distribution and potential energy profile for the reaction without a catalyst.

Annotate both charts to show the activation energy for the catalysed reaction, using the label _E_a (cat).

a(iii).

Explain how the catalyst increases the rate of the reaction.

a(iv).

Solid copper(II) chloride absorbs moisture from the atmosphere to form a hydrate of formula CuCl2•xH2O.

A student heated a sample of hydrated copper(II) chloride, in order to determine the value of x. The following results were obtained:

Mass of crucible = 16.221 g
Initial mass of crucible and hydrated copper(II) chloride = 18.360 g
Final mass of crucible and anhydrous copper(II) chloride = 17.917 g

Determine the value of x.

State how current is conducted through the wires and through the electrolyte.

Wires:

Electrolyte:

c(i).

Write the half-equation for the formation of gas bubbles at electrode 1.

c(ii).

Bubbles of gas were also observed at another electrode. Identify the electrode and the gas.

Electrode number (on diagram):

Name of gas:

c(iii).

Deduce the half-equation for the formation of the gas identified in (c)(iii).

c(iv).

Determine the enthalpy of solution of copper(II) chloride, using data from sections 18 and 20 of the data booklet.

The enthalpy of hydration of the copper(II) ion is −2161 kJ mol−1.

Calculate the cell potential at 298 K for the disproportionation reaction, in V, using section 24 of the data booklet.

e(i).

Comment on the spontaneity of the disproportionation reaction at 298 K.

e(ii).

Calculate the standard Gibbs free energy change, Δ_G_θ, to two significant figures, for the disproportionation at 298 K. Use your answer from (e)(i) and sections 1 and 2 of the data booklet.

e(iii).

Suggest, giving a reason, whether the entropy of the system increases or decreases during the disproportionation.

e(iv).

Deduce, giving a reason, the sign of the standard enthalpy change, Δ_H_θ, for the disproportionation reaction at 298 K.

e(v).

Predict, giving a reason, the effect of increasing temperature on the stability of copper(I) chloride solution.

e(vi).

Describe how the blue colour is produced in the Cu(II) solution. Refer to section 17 of the data booklet.

f(i).

Deduce why the Cu(I) solution is colourless.

f(ii).

When excess ammonia is added to copper(II) chloride solution, the dark blue complex ion, [Cu(NH3)4(H2O)2]2+, forms.

State the molecular geometry of this complex ion, and the bond angles within it.

Molecular geometry:

Bond angles:

f(iii).

Examine the relationship between the Brønsted–Lowry and Lewis definitions of a base, referring to the ligands in the complex ion [CuCl4]2−.

f(iv).

(i) Calculate Δ_H_θ, in kJ, for this similar reaction below using Δ H f θ data from section 12 of the data booklet. Δ H f θ of HOCH2CH2OH(l) is –454.8kJmol-1.

2CO (g) + 3H2 (g) ⇌HOCH2CH2OH (l)

(ii) Deduce why the answers to (a)(iii) and (b)(i) differ.

(iii) Δ_S_θfor the reaction in (b)(i) is –620.1JK-1. Comment on the decrease in entropy.

(iv) Calculate the value of ΔGθ, in kJ, for this reaction at 298 K using your answer to (b)(i). (If you did not obtain an answer to (b)(i), use –244.0 kJ, but this is not the correct value.)

(v) Comment on the statement that the reaction becomes less spontaneous as temperature is increased.

Predict the 1HNMR data for ethanedioic acid and ethane-1,2-diol by completing the table.