The ratio of the initial to the final pressure of a given mass of gas is 1:1.5. Calculate the final volume of the gas if the initial volume was 300cm³ ?at the same temperature.

• A) 120cm³
• B) 200cm³
• C) 450cm³
• D) 750cm³

In the course of purifying water for town supply the water is passed through large settlings tanks, containing sodium aluminate (III) to remove

• A. large particles
• B. germs
• C. fine particles
• D. odour

Hydrocarbons which will react with Tollen's reagent conform to the general formula

• A) CnH2n
• B) CnH2n+2
• C) CnH2n−2
• D) CnH2n+1OH

An example of aliphatic unsaturated hydrocarbon is

• A. pentane
• B. butanol
• C. propene
• D. benzene

Which of the following hydrohalic acids is the weakest?

• A. HBr
• B. HCI
• C. HF
• D. HI

Consider the reaction represented by the equation: 2H2SO 4(aq0 + C(s) → 2H2O(l) + 2SO2(g) + CO 2(g) H2SO 4 is acting as

• A. a catalyst
• B. an oxidizing agent
• C. a reducing agent
• D. a sulphonating agent

Oil spillage in ponds and creeks can be cleaned up by

• A) burning off the oil layer
• B) spraying with detergent
• C) dispersal with compressed air
• D) spraying with hot water

Lithium with atomic number of 3 is a

• A) Strong reducing agent
• B) Strong oxidizing agent
• C) Weak reducing agent
• D) Weak oxidizing agent

(a) In an equilibrium reaction between gases Q and R, to form QR, the energy content of the reactants is 100 KJ and that of the product is 54 kJ. The energy content of the activated complex is 210 KJ.

(i) Draw an energy profile diagram for the reaction. (ii) Determine the: I. activation energy of the reaction il. enthalpy change ΔH of the reaction. (iii) Write a balanced equation for the reaction. (iv) Give a reason for the answer given in 3(C)(iv). (iv) State whether the reaction is exothermic or endothermic.

(b) Consider the following table:

(i) Write the electron configuration for each of the elements. Element E, F, G, H 12 13 (ii) State: I. two elements that are metals; II. the elements(s) most likely to form an ion with a charge of +3; III. the element(s) which belong(s) to group VII. on the periodic table; IV. the formula of the compound formed between F and G. Atomic

(c) Define the term isotopy (d) Name the three building blocks of matter.

The weakest attractive force that can be observed between two molecules is

• A) ionic
• B) covalent
• C) coordinates
• D) van der waals forces