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(a) (i) Nitrogen and hydrogen
(ii) Platinum
(iii) 4NH3(g) + 5O2(g)-------> Platinum 4NO(g) + 6H2O(g)
(iv) Neutralization
(v) The concentrated nitric acid oxidizes sulphur to sulphuric VI acid. The acid is
reduced to nitrogen (IV) oxide
S(s) + 6HNO3(l)--------> H2SO4(aq) + 6NO2(g) + 2H2O(l)
(vi) Any metal above copper but below sodium in the reactivity series.
(vii) (i) J – NH4NO3
(ii) Molar mass NH4NO3 = 28 + 4 +48 = 80g
Therefore 80g of NH4NO3 contain 28g of nitrogen
14g of nitrogen would be contained in 14/28 x 80
= 40g of NH4NO3
(b) (NH4)3 PO4 is less soluble hence it is less easily leached from the soil.
-(NH4)3 PO4 ( provides the plant with nitrogen and phosphorous.
sharon kalunda answered the question on May 17, 2019 at 09:21
- The grid given below represents part of the periodic table. Study it and answer the questions
that follow. The letters are not the actual symbols of...(Solved)
The grid given below represents part of the periodic table. Study it and answer the questions
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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Below are the bond dissociation energies of some elements.
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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The diagram below outlines industrial preparation of bleaching powder.
(i) Give the chemical name of bleaching powder
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(iii) Explain why water in which bleaching powder has been added needs a lot of soap
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Date posted: May 17, 2019. Answers (1)
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(i) Identify gas Q
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Date posted: May 17, 2019. Answers (1)
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On heating Ammonium Chloride two gas P and J were evolved G turned moist litmus
paper red and J turned Moist litmus paper blue. On cooling , the two gases
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)
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Dry hydrogen chloride gas was passed through heated iron wire as shown in the diagram
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
b) Identify product Q
c) The total mass of product Q formed was found to be 5.3g. Calculate the volume of
chlorine gas used.
(Cl = 35.5, Fe= 56, Molar gas volume at room temperature = 2400cm3)
Date posted: May 17, 2019. Answers (1)
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The flow chart below outlines some of the process involved during extraction of copper.
(i) Write the formula of copper pyrite.
(ii) Name liquid T
(iii) Write equations for the reactions taking place in the 2nd roasting furnace.
(iv) Identify substance B and write equation for the reaction that take place in the smelting furnace.
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Date posted: May 17, 2019. Answers (1)
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(ii) Name the compounds C and E.
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The graph below was obtained from an experiment used to investigate the reaction
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Date posted: May 17, 2019. Answers (1)
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Describe two observable characteristics of a luminous flame.
Date posted: May 17, 2019. Answers (1)
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Write a chemical equation for the combustion of laboratory gas , when the
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Date posted: May 17, 2019. Answers (1)
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copper (II) sulphate solution, while aluminium chloride cannot be extracted by...(Solved)
Explain why during the extraction of metals, copper can be extracted by the electrolysis of
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Date posted: May 17, 2019. Answers (1)
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Study the following equilibrium equation and answer the questions that follows.
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Date posted: May 17, 2019. Answers (1)
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The following are standard electrode potentials of some half-cell reactions. Use the data to
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i) Suggest the identify of element U.
ii) Draw a labeled diagram of an electrochemical cell that would produce the largest e.m.f.
Date posted: May 17, 2019. Answers (1)
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The following diagram represents a set-up used to investigate conditions necessary for rusting of iron.
After several days it was found that the nails did not rust. Identify solid P.
Date posted: May 17, 2019. Answers (1)
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The following diagram was used to investigate the electrolysis of copper(II) Sulphate solution
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When a fixed current was passed through the two electrolytic cells as shown, 1.27g of copper
and 0.6g of G were deposited at the respective electrodes,. Calculate the numerical value
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(Cu=63.5; g = 60; 1 Faraday = 96500C)
Date posted: May 17, 2019. Answers (1)
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In the chemistry laboratory, both blue and red litmus papers are used to test for the nature
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Date posted: May 17, 2019. Answers (1)