In the purification of impure samples of ethyl ethanoate synthesized by esterification, concentrated sodium trioxocarbonate (IV) solution is used to remove

• A. water
• B. basic impurities
• C. acidic impurities
• D. ethoxyethane

(a) If a steel spoon were to be plated with silver, state what would be suitable for use as the;

(i) anode. (ii) cathode; (iii) electrolyte

(b)(i) Write an equation for one of the reactions involved in the purification of bauxite.

(ii) Give the reason why the carbon anodes are changed at intervals during the electrolysis of pure alumina solution in molten cryolite.

What is the molecular geometry of a molecule with three bonding pairs and no lone pairs around the central atom?

• A. Tetrahedral
• B. Trigonal planar
• C. Linear
• D. Octahedral

(a)(i) What is meant by the activation energy of a reaction?

(ii) State the effect of a catalyst on activation energy.

(b) What substance serves as a catalyst in each of the following?

(I) Hydrogenation of oils

(ii) Biochemical reactions.

The pH of four solutions M,N,Q and R are 2,6,8 and 11 respectively. Which of the following deductions about the solutions is correct?

• A. The pH of N is increased when the solution is diluted
• B. The pH of Q is increased when the solution is evaporated
• C. M is the most alkaline solution
• D. R is the most acidic solution

The following table gives the atomic numbers of elements V, W, X, Y and Z.

(a)Which of the elements: (i) belong(s) to group 1?

(ii) is/are riotle gas(es)?

(iii) form(s) coloured compound(s)?

(iv) form(s) an anion?

(v) react(s) with water to liberate hydrogen?

(vi) react(s) with water to form alkaline solution?

(b) What is the:

(i) charge on the ion formed in

(a)(iv) above?

(ii) group of the element(s) in (a)(i) above?

(c)(i) Write the formula of the compound formed between element V and element W.

(ii) Sate the type of bond formed in (c)(i) above. Explain your answer.

(d)(i) What is a covalent compound?

(ii) Give two factors that influence covalent bonding.

(iii) State the type of bond that exists in each of the following substances: MgO, NH\(_3\) and Fe.

(iv) What are intermolecular forces?

Which of these is constant R for ideal gas?

• A)
  8.314jkmol\(^{-1}\)
• B)
  8.314\(^{-1}\)jkmol\(^{-1}\)
• C)
  8.314jkmol
• D)
  8.314Jk\(^{-1}\)mol\(^{-1}\)

An element X has two isotopes, \(^{65}X_{30}\) and \(^{66}X_{30}\) with relative abundance of 60 % and 40% respectively. The relative atomic mass of X is

• A. 66.00
• B. 65.50
• C. 65.00
• D. 65.40

Which of these mathematical relationships is for Charles law?

• A)
  \(V = K(\frac{1}{P})\)
• B)
  \(V = K\frac{T}{P}\)
• C)
  \(V = KT\)
• D)
  \(V = K\frac{1}{T}\)

The oxidation number of iodine in KIO₃is

• A) +7
• B) +3
• C) +5
• D) +6