(a) (i) Molten aluminium oxide.
(ii) Aluminium metal.
(iii) Anode.
(b) Carbon.
(c)(i) Al3+ + 3e--------> Al(s)
(ii) Oxygen gas evolved at E reacts with the carbon electrode to form CO2(g).Hence it is consumed.
(iii) To lower the melting point of Al2O3 so as to conserve energy.
sharon kalunda answered the question on May 17, 2019 at 10:39
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In an experiment to determine the molar heat of neutralization of hydrochloric acid
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hydrochloric acid with 50cm3 of 2M sodium hydroxide solution. They obtained the following results.
Initial temperature of acid = 25.00C
Initial temperature of base = 25.00C
Highest temperature reached
With the acid – alkali mixture = 34.00C
(a) Write an ionic equation for the neutralization reaction between hydrochloric acid
and sodium hydroxide.
(b ) Calculate :
(i) The change in temperature.
(ii) The amount of heat produced during the reaction.
( Specific heat capacity of solution = 4.2 kJkg-1k-1 )
(iii) The molar heat of neutralization of sodium hydroxide.
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(b) Write an equation for the reaction taking place.
(c ) State two different ways by which the reaction could have been made more rapid.
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answer the questions that follow.
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(ii) What catalyst is used in step I ?
(iii) Write an equation for the reaction that occurs between ammonia and oxygen in
presence of the catalyst.
(iv) Identify the process in step II
(v) Using an appropriate equation, explain how the reaction in step III occurs ?
(vi) What should be added to solution K to form solid L ?
(vii) (a) (i) Write the formula of compound J.
(ii) Calculate the mass of compound J that would contain 14g of nitrogen
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(b) State two advantages of ammonium phosphate over ammonium nitrate.
Date posted: May 17, 2019. Answers (1)
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(ii) Write the chemical formula of the sulphate of element D.
(iii ) Which letter represents the most reactive
(a) Metal
(b) Non-metal
(iv) Name the bond formed when B and H react. Explain your answer.
(v) Select one element that belong to period 4.
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Date posted: May 17, 2019. Answers (1)
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a) (i) How can the identity of the substance burning with flame Z be confirmed.
(ii) What is observed in combustion tube during the experiment?
(iii) Write the equation for the reaction taking place in the combustion tube.
(iv) Chlorine gas was passed over the product obtained in the combustion tube to give
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