Chemistry Past Questions and Answers

Which of the following is required in an experiment to determine the enthalpy of solution of anhydrous CuSO? l. Mass of the anhydrous CuSO <sub style='font-size: smaller;'>4</sub> II. Volume of water in which the CuSO<sub style='font-size: smaller;'>4</sub> is dissolved lll. lnitial temperature of water lV. Final temperature of the solution

Which of the following pollutants is biodegradable?

The process of seeding during the extraction of aluminium involves the addition of pure AI(OH)<sub style='font-size: smaller;'>3</sub> crystals in order to

Which of the following measures is not suitable for controlling water pollution?

(a)(i) Mention two types of bond present in the ammonium ion<br/>(ii) Give three characteristic properties of electrovalent compounds<br/>(iii) State. two differences between chemical reactions and nuclear reactions<br/> <br/>(b) Two elements represented by the letters and Y have atomic numbers 9 and 12 respectively.<br/>(i) Write the electronic configuration of X using the s,p,d, notation<br/>(ii) To what group does Y belong in the periodic table?<br/>(iii) Write the formula of the compound formed when X copibines with Y<br/>(iv) Explain wily X is a good oxidizing agent<br/>(v) State with reason, whether Y would be expected to form acidic or basic oxide<br/> <br/>(c) Balance the following nuclear equations and identify the particles represented by X and Y.<br/>(i) \(^{14}_6C\) \(\to\) X + \(^{14}_7N\)<br/>(ii) \(^{14}_7C\)<br/>Y \(\to\) \(^1_1H\) + \(^{17}_8O\)<br/> <br/>(d) Consider the following list of substances: Carbon (IV) oxide, hydrogen, zinc, sulphier, methane, potassium and mercury. From the list above, state the:<br/>(i) elements that are metals<br/>(ii) compounds that are gases at room temperature<br/>(iii) non-metals that are solids at room temperature