Both ammonia and Calcium hydroxide solutions
(a) React acids//dilute acids to form salt and water only
(b) Have pH value above 7
(c) Turn red litmus to blue
(d) Turn phenolphthalein indicator from colourless to pink
(e) Turn methyl orange to pink
sharon kalunda answered the question on May 17, 2019 at 10:47
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Date posted: May 17, 2019. Answers (1)
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process is 4,000 amperes. Study the diagram and answer the questions that follow.
(a) Name:
(i) Electrolyte A
(ii) Substance D
(iii) Electrode E
(b) Name the material from which the electrodes are made.
(c ) (i) Write the equation that produces aluminium metal.
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(iii) Why is cryolite added to the electrolyte before the process of electrolysis ?
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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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(d) Draw an energy level diagram for the reaction.
Date posted: May 17, 2019. Answers (1)
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A piece of marble chip ( calcium carbonate) is put in a beaker containing excess of dilute hydrochloric
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(a) Why is there a continuous loss of mass of the reaction mixture.
(b) Write an equation for the reaction taking place.
(c ) State two different ways by which the reaction could have been made more rapid.
(d) Why does the mass remain constant after 8 minutes.
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(c ) At what electrode does reduction take place. Explain your answer.
(d) State the most suitable electrodes that can be used in this experiment.
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answer the questions that follow.
(i) List the raw materials used in the manufacture of ammonia.
(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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(i) What name is given to the family of elements to which A and C belong?
(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.
(vi) Ionic radius of element E is bigger than the atomic radius. Explain.
(vii) The electron configuration of a divalent anion of element N is 2.8.8. Induce the
position of element N on the periodic table drawn above.
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Date posted: May 17, 2019. Answers (1)
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Use this information to calculate the heat of reaction for:-
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below
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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a) State one precaution that should be taken. Explain
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Date posted: May 17, 2019. Answers (1)