CuSO₄.5H₂O can be obtained from an aqueous solution of copper (ll) tetraoxosulphate (VI) by

• A. evaporation to dryness
• B. using chromatography
• C. precipitation
• D. crystallization

(a) What term is used to describe each of the following processes?

(i) Alkaline hydrolysis of fats and oils;

(ii) The conversion of glucose into ethanol by enzymatic action;

(iii) Thermal decomposition of higher petroleum fractions into lower molecular mass hydrocarbons in the presence of catalyst.

(b)(i) Write the structure and IUPAC name for one alkanoic acid with the molecular formula C\(_4\)H\(_8\)0\(_2\).

(ii) Arrange the following compounds in order of increasing boiling point: Butane; Butanoic acid; Methylpropane.

(iii) Give an explanation for your answer in (b)(ii).

(c)(i) Ethanol was used for preparing a gas X which decolorized bromine water. Identify X and describe briefly its laboratory preparation.

(ii) Write an equation to show how ethanol reacts with sodium

(iii) Give the reagent and reaction conditions for the conversion of ethanol into C\(_2\)H\(_5\)COOC\(_2\)H\(_5\).

(d) State the type of recction involved in each of the conversions indicated below:

(i)C\(_6\)H\(_6\)C\(_6\)H\(_5\)CH\(_3\)

(ii) nC\(_2\)H\(_4\) \(\to\) (CH\(_2\) - CH\(_2\)),

(iii) CH\(_3\)CH\(_2\)CH(OH)CH\(_3\) -> CH\(_3\)CH\(_2\)CCH\(_3\)

(iv) (C\(_6\)H\(_{10}\)O\(_5\)) -> C\(_6\)H\(_{12}\)O\(_6\).

(iv)

Which of the following compounds will leave a metal residue when heated?

• A. Cu(NO₃)₂
• B. AgNO₃
• C. K2CO₃
• D. CaCO₃

The energy value of petrol can be determined by a

• A. bomb calorimeter
• B. catalytic cracker
• C. fractionating column
• D. thermometer

Which of the following compounds can be represented by the molecular formula C₂H₆O?

• A. Propanel
• B. Ethanol
• C. Methanoic acid
• D. Glucose

A visible change is observed when a strip of iron is placed in an aqueous solution of A

• A. FeSO₄
• B. ZnSO₄
• C. CuSO₄
• D. MgSO₄

Consider the following equation; Cr₂O₇(aq)^2- + 14H⁺(aq) + 6e^- → 2Cr³⁺(aq) + 7H₂O(I). The oxidation number of chromium changes from

• A. -2 to + 3
• B. - 2 to + 6
• C. + 6 to + 3
• D. + 7 to + 6

Which of the following types of alkanols undergo oxidation to produce alkanoic acids? 1. Primary alkanols 11. Secondary alkanols 111. Tertiary alkanols

• A. I, II and III
• B. l and ll only
• C. ll only
• D. l only

Which of the following substances increases in mass when heated in air?

• A. Sodium chloride
• B. lodine crystals
• C. Magnesium ribbon
• D. Copper (ll) oxide

(a) Explain in terms of the kinetic theory why a tyre should not be overinflated.

(b)The following results were obtained at room temperature in an experiment to verify one of the gas laws using a glass syringe:

(i) Plot a graph of P against \(\frac{1}{v}\), using 1 cm to represent 0.01 atm on the vertical axis and 1cm to represent 0.02 unit on the horizontal axis.

(ii) Which of the gas laws is in agreement with the results?

(c) The flow chart below represents the stages involved in the manufacture of H\(_2\)SO\(_4\).

+x +Conc. H\(_2\)SO\(_4\) +H\(_2\)O

S + O\(_2\) \(\to\) SO\(_2\) \(\to\) SO\(_3\) \(\to\) Y \(\to\) Conc H\(_2\)SO\(_4\)

stage I stage II stage III stage IV

(i) Name the process represented by the chart.

(ii) Identify reactant X and product Y.

(iii) What are the operating temperature and pressure at stage II?

(iv) Mention the stage which requires a catalyst and state the catalyst used.

(v) Give the reason why the SO\(_3\) produced in stage II is not dissolved directly in water to form the acid

(d) When K\(_4\)Cr\(_2\)C\(_7\) dissolves in water, the following equilibrium is established:

Cr\(_2\)O\(^{2-}_{7(aq)}\) + H\(_2\)O\(_{(l)}\) \(\to\) 2CrO\(^{2-}_{4(aq)}\) + 2H\(_{aq}\)

(i) State the colour observed on adding a few drops of dilute H\(_2\)SO\(_4\) to the system.

(ii) Explain your answer in (d)(1).

(iii) What principle is applicable to this explanation?