Chemistry Random Retrieval Y13

What is the main organic product when benzene reacts with 2-iodo-2-methylpropane in the presence of aluminium chloride?

Which types of change are involved in this sequence of reactions, though not necessarily in the order listed?

CH₃CO-C₆H₅ -> CH₃CO-C₆H₄-NO₂ -> CH₃CHOH-C₆H₄-NO₂ -> CH₃CH(OCOCH₃)-C₆H₄-NO₂

(i) esterification

(ii) reduction

(iii) nitration

(iv) hydrolysis

Glycine reacts with dilute hydrochloric acid to form:

Step 2:

This is the ¹H NMR spectrum of:

Which technique would you use to measure the rate of reaction for the hydrolysis of ethyl ethanoate?

Consider the following reaction:

C₄H₉Cl_(aq) + OH^-_(aq) => C₄H₉OH_(aq) + Cl^-_(aq)

The rate equation was found, by experiment:

rate = k [C₄H₉Cl]

Which of the following statements is/are true?

(i) Increasing the concentrations of all reactants speeds up the nucleophilic substitution reaction

(ii) The mechanism probably has only one step

(iii) There are two particles involved in the rate determining step

(iv) OH^- is required for the overall reaction to proceed

Which first-row d-block metal forms hydrated ions in the +3 state which undergo a ligand exchange reaction to form a deep red complex ion with thiocyanate ions, SCN^-.

What solution concentrations are required for the determination of a standard cell potential, E^ϴcell/V?

What is the value of E^ϴcell/V observed for a cell constructed from the following half-cells?

Fe³⁺_(aq) + e^- <=> Fe²⁺_(aq) E^ϴ/V = +0.77

MnO₄^-_(aq) + 8H⁺_(aq) + 5e^- <=> Mn²⁺_(aq) + 4H₂O_(aq) E^ϴ/V = +1.51

Work out the ratio of the species in the following half-equation.

C₂O₄^2- => CO₂ + e^-

Work out the ratio of the species in the following half-equation.

O₂ + e^- + H⁺ => H₂O

Using oxidation numbers (states) work out the ratio of the species in the following half-equation.

H₂O₂ + H⁺ + e^- => H₂O

Look at the chemical equation below.

2NaHCO_3(s)=> Na₂CO_3(s)+ H₂O_(g)+ CO_2(g)

By selecting the appropriate data from the ‘Selection of Thermodynamic Data’ in TOOLS, calculate the enthalpy change ΔH^Ɵ for the process. Take care with states!

Consider the following equilibrium:

3Fe_(s) + 4H₂O_(g) Fe₃O_4(s)+ 4H_2(g)

40.0 g of iron wool was placed in a vessel of volume 2.00 dm³. The iron was exposed to 20.0 mol of high pressure steam and the system allowed to settle to equilibrium. At equilibrium, 0.250 mol of hydrogen was found in the vessel. The gauge on the pressure vessel read 1 000 kPa. The volume of iron wool was insignificant.

Calculate the value of K_p (no units) under these conditions.

Consider the following equilibrium for the Haber-Bosch process:

3H_2(g) + N_2(g) <=>2NH_3(g)

32.0 mol of H₂ was combined with 12.0 mol of N₂ and the mixture sealed and pressurised in a vessel of volume 2.00 dm³. The mixture was left until no further observable change in composition took place. At this point, 4.00 mol of NH₃ was found to be present in the mixture. The pressure was recorded as 200 000 kPa.

Calculate the value of K_c (in units: mol^-2 dm⁶) under these conditions.

Consider the following equilibrium:

2SO_2(g) + O_2(g) <=>2SO_3(g)

8.00 mol of SO₂ was mixed with 5.00 mol of O₂ and the mixture sealed in a heated vessel of volume of 1.00 dm³. The mixture was left until no further observable change in composition took place. At this point, 2.00 mol of O₂ was present in the mixture and the pressure was recorded as 200 kPa.

Calculate the value K_c (in units: mol^-1 dm³) under these conditions.

By inspection of this experimental data, what is the rate equation for this reaction?

The graph from an experiment to study the decomposition of hydrogen peroxide shows how the concentration of the hydrogen peroxide varied with time at constant temperature.

Time = 0 minutes, [H₂O₂] = 0.020 mol dm^-3

Time = 654 minutes, [H₂O₂] = 0.010 mol dm^-3

Time = 1308 minutes, [H₂O₂] = 0.005 mol dm^-3

This suggests that, under the conditions of the experiment:

(i) the reaction is zero order with respect to hydrogen peroxide

(ii) the concentration after 1962 minutes was 0.0025 mol dm^-3

(iii) the rate of reaction was constant for the first 654 seconds

(iv) the half-life of the reaction was 654 minutes

An alloy of platinum with rhodium is the catalyst used:

(i) in catalytic converters to cut pollution from motor vehicles

(ii) in the synthesis of ammonia from nitrogen and hydrogen

(iii) in the oxidation of ammonia to NO_(g) during the manufacture of nitric acid

(iv) in the hydrogenation of vegetable oils.

This is the ¹H NMR spectrum of:

How many peaks would you expect to see in the ¹³C spectrym of 2,5-dimethyltetrahydrofuran?

Which of these compounds are chiral?

(i) propan-1-ol,

(ii) propan-2-ol,

(iii) butan-1-ol,

(iv) butan-2-ol

Which of these types of isomerism are examples of stereoisomerism.

(i) chain isomerism

(ii) E/Zisomerism

(iii) functional group isomerism

(iv) optical isomersim

Which of these compounds are chain isomers of 2-methylpentane

(i) hexane,

(ii) 2,2-dimethylpentane,

(iii) 2,3-dimethylbutane,

(iv) 2,2-dimethylpropane

The nitrating agent for benzene is a mixture of concentrated sulfuric and nitric acids. This mixture produces:

Step 1:

Step 2:

Which of these amino acids are chiral?

(i) CH₃CHNH₂CO₂H

(ii) C₆H₅CH₂CHNH₂CO₂H

(iii) HOCH₂CHNH₂CO₂H

(iv) CH₂NH₂CO₂H

What is the organic product when benzene reacts with ethanoyl chloride in the presence of aluminium chloride?