Chemistry Year 13 Random Retrieval

Which of these properties of benzene are associated with the presence of delocalised electrons?

(i) There are no isomers of 1,2-dichlorobenzene

(ii) Benzene is more stable than might otherwise be expected

(iii) Benzene typically undergoes substitution rather than addition reactions

(iv) Benzene reacts with nucleophiles

The relative rates of hydrolysis for these halogenoalkanes are in the order

C₄H₉I > C₄H₉Br > C₄H₉Cl

This trend correlates with the:

This is the ¹H NMR spectrum of:

This is the ¹H NMR spectrum of:

What does the symbol [X] represent?

pH = 2.9 for a solution which contains equal concentrations of chlorethanoic acid and sodium chlorethanoate. What is the pH of the solution after mixing it with twice its own volume of pure water?

The standard enthalpy change when one mole of an ionic compound forms from free gaseous ions is called the:

For which of these species is the value of the electron affinity positive?

(i) F

(ii) Cl

(iii) O

(iv) O^-

Look at the chemical equation below.

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

Using your answers to Questions 1 and 2, calculate the Gibbs Energy change, ΔG, for the process if it is carried out in an oven at 100^oC.

If this question is from a Random Retrieval, you can also carry out this calculation by first working out values for ΔS^Ɵ and ΔH^Ɵ by selecting the appropriate data from the ‘Selection of Thermodynamic Data’ in TOOLS.

Which of the statements below are true of this reaction?

[Cu(H₂O)₆]²⁺(aq) + 4NH₃(aq) <=> [Cu(NH₃)₄(H₂O)₂]²⁺(aq) + 4H₂O(aq)

(i) Copper disproportionates,

(ii) It is a proton transfer reaction,

(iii) Ammonia is oxidised,

(iv) It is a ligand exchange reaction