Which of the following represents the anodic and cathodic reactions during the extraction of aluminium?Anode Cathode(A) 2O2- + 4e →→ O2 AI →→ AI3+ + 3e(B) 4OH- →→ 2H2O + O2 + 4e AI3+ + 3e →→ AI(C) AI3 ++ 3e →→ AI2O2- →→ O2 + 4e(D) 2O2- →→ O2 + 4eAI3 ++ 3e →→ AIA(A)B(B)C(C)D(D)

Which of the following statements is true?Metal ions always gain electrons at the anodeMetal ions always gain electrons at the cathodeMetal ions always lose electrons at the anodeMetal ions always lose electrons at the cathode2How is aluminium extracted from the earth?As an aluminium ore known as bauxiteAs pure aluminiumAs an aluminium ore known as cryoliteAs aluminium oxide3In the electrolysis of aluminium oxide, the electrodes are made of carbon in the form of graphite. Which of the following statements is not true?The presence of carbon electrodes reduces the amount of energy required for the electrolysis reactionGraphite is used as an electrode because it is a good conductor of electricityCarbon is relatively unreactive, and the electrodes do not therefore react with the aluminium oxide during electrolysisAt extremely high temperatures, the oxygen produced during electrolysis reacts with the carbon anode to form carbon dioxide4Why is molten cryolite mixed with the aluminium oxide prior to electrolysis?To act as a conductor of electricityTo increase the temperature required for the reactionTo hold the electrodes in placeTo lower the temperature required for the reaction5What is the balanced equation for the electrolysis of aluminium oxide?3Al2O3(l) → 6Al(l) + 3O2(g)2Al2O3(l) → 4Al(l) + 3O2(g)Al2O3(l) → Al(l) + O2(g)2Al2O3(l) → 3Al(l) + 4O2(g)

Study the flow chart of extraction of aluminium below and answer the questions that follow. i) Write the equation for the reaction in chamber Q. (1 mark ii) Name residue P. (1 mark) iii) Name processes R and C. (2 marks)Residue P Bauxite Process R NaOH (aq) Q Solution J Process B Process C Aluminium liquidAl2O3(s)AlOH) 3 (aq) Bauxite Grinders Filtration containing Al(OH)4(aq) / AlO2(aq) Residue Aluminium Hydroxide Aluminium Oxide Molten Aluminium Oxide Gas R Molten Aluminium Process V Process T iv) In process C, a current of 88.0A was passed through molten aluminium oxide for 8 hours. Determine the mass of aluminium produced. (3 marks) (1 Faraday = 96 500 coulombs and Al = 27) v) State two ways by which process B is accomplished. (2 marks) vi) Write an equation for the conversion of aluminium hydroxide into aluminium oxide. (1 mark) b) Explain the following observations: i) Aluminium utensils should not be cleaned with strongly alkaline washing liquids. (1 mark) ii)Aluminium alloys are commonly used in aeroplane construction

Study the flow chart of extraction of aluminium below and answer the questions that follow.(i) Write the equation for the reaction in chamber Q.(1 mark) ……………………………………………………………………………………………………………… (ii) Name residue P.(1 mark) ………………………………………………………………………………………………… .(iii) Name processes R and C. (2marks) R………………………………………………………………………………………………….. C………………………………………………………………………………………………….. (iv) In process C, a current of 88.0A was passed through molten aluminium oxide for 8hours. Determine the mass of aluminium produced.(3marks) (1 Faraday = 96 500 coulombs and Al = 27)Residue PBauxiteProcess R NaOH(aq) QSolution JProcess BProcess CAluminiumAl2O3(s) Al(OH)3 (s) CHEMISTRY REVISION 2020 Page 2(v) State two ways by which process B is accomplished. (2marks) ……………………………………………………………………………………………………………………… ……………………………………………………………………………………………………………………… (vi) Write an equation for the conversion of aluminium hydroxide into aluminium oxide.(1mark)…………………………………………………………………………………………………………… (b) Explain the following observations:(i) Aluminium utensils should not be cleaned with strongly alkaline washing liquids. (1mark)………………………………………………………………………………………………………………… ………………………………………………………………………………………………………..……… (ii)Aluminium alloys are commonly used in aeroplane construction. (1mark)

Aluminium is manufactured by the electrolysis of aluminium oxide dissolved in molten cryolite.At the anode, oxide ions react to make oxygen molecules.Construct the ionic half-equation for this electrode reaction

In the electrolytic refining of copper, what reaction occur at the cathode?Select one:a.Cu depositionb.H⁺ reductionc.Cu oxidationd.Cu²⁺ oxidation