(i) Zn(s) + HNO3(aq) - HNO3 is oxidizing agent, H2O immediately.
(ii) Pb(s) + HCl(aq) - PbCl2 formed is insoluble, prevents further reaction.
(iii) K(s) + H2SO4(aq) - Reaction of K(s) with H2SO4(aq) is explosive
sharon kalunda answered the question on May 17, 2019 at 11:21
- Give names of the following processes used to:
(Solved)
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Date posted: May 17, 2019. Answers (1)
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Date posted: May 17, 2019. Answers (1)
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Date posted: May 17, 2019. Answers (1)
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Date posted: May 17, 2019. Answers (1)
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Aluminium is extracted from its ore by electrolysis method. The current required in the
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.
(ii) Explain why E has to be replaced from time to time.
(iii) Why is cryolite added to the electrolyte before the process of electrolysis ?
Date posted: May 17, 2019. Answers (1)
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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.
(c) Write the thermochemical equation for the reaction.
(d) Draw an energy level diagram for the reaction.
Date posted: May 17, 2019. Answers (1)
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Date posted: May 17, 2019. Answers (1)
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Date posted: May 17, 2019. Answers (1)
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acid which is placed on a reading balance....(Solved)
A piece of marble chip ( calcium carbonate) is put in a beaker containing excess of dilute hydrochloric
acid which is placed on a reading balance. The mass of the beaker and its contents is recorded every
two minutes, as shown in the table.
(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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Date posted: May 17, 2019. Answers (1)
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i)Arrange the metals in order of reactivity.
ii)Calculate the E.M.F of the cell shown below.
iii) What would happen if a cell with chlorine and zinc ions, the anode was made
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Date posted: May 17, 2019. Answers (1)
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The set-up below represents electrolysis of dilute sulphuric (VI) acid.
(a) Identify gases M and N
(b) Write an ionic equation for the production of gas M.
(c ) At what electrode does reduction take place. Explain your answer.
(d) State the most suitable electrodes that can be used in this experiment.
Explain your answer.
Date posted: May 17, 2019. Answers (1)
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Date posted: May 17, 2019. Answers (1)
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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
( H = 1, N = 14, O = 16 )
(b) State two advantages of ammonium phosphate over ammonium nitrate.
Date posted: May 17, 2019. Answers (1)
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that follow. The letters are not the actual symbols of...(Solved)
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that follow. The letters are not the actual symbols of the elements.
(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.
(viii) The oxide of G has a lower melting point than the oxide of L. Explain.
(ix) How do the atomic radii of I and C compare. Explain.
(x) Explain the trend in the 1st ionization energies of the elements J, I and L.
Date posted: May 17, 2019. Answers (1)
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Use this information to calculate the heat of reaction for:-
Date posted: May 17, 2019. Answers (1)
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(Solved)
Study the arrangement below and answer the question that follows.
Explain what will be observed after some time.
Date posted: May 17, 2019. Answers (1)
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(i) Give the chemical name of bleaching powder
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Date posted: May 17, 2019. Answers (1)
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Date posted: May 17, 2019. Answers (1)
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recombined to form a white solid
a) Identify P and J
b) What property of Ammonium Chloride is shown in this experiment?
Date posted: May 17, 2019. Answers (1)