(a) Write the electron arrangement of:
(i) ion of S - 2.8
(ii) atom of T - 2.8.4
(b) Explain why the melting point of T is higher than that of U.
Atoms are covalently bonded together to form a giant atomic structure. Atoms of U are bonded covalently
to form molecules. The molecules are then hold together by weak Van der waals to form a simple molecule structure.
maurice.mutuku answered the question on September 12, 2019 at 08:44
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(i) Obtain an equation of the cell reaction.
(ii) Calculate the 
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(iii) Give the oxidizing species.
Date posted: September 12, 2019. Answers (1)
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Date posted: September 12, 2019. Answers (1)
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Date posted: September 12, 2019. Answers (1)
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(a) Identity solid X.
(b) Write an ionic equation for the reaction between P and copper (II) sulphide solution.
(c) State the observation made when gas P is bubbled through iron (III) chloride solution.
Date posted: September 12, 2019. Answers (1)
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Date posted: September 12, 2019. Answers (1)
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Date posted: September 12, 2019. Answers (1)
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Date posted: September 12, 2019. Answers (1)
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Date posted: September 12, 2019. Answers (1)
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State, giving a reason what would happen to the equilibrium if;
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(ii) Hydrogen chloride is bubbled into the equilibrium mixture.
Date posted: September 12, 2019. Answers (1)
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Date posted: September 12, 2019. Answers (1)
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(specific heat capacity of water = 4.2kJ/kg/k...(Solved)
When a sample of ethane was burnt, the heat provided raised the temperature of 500cm3 of water by 21.5k
(specific heat capacity of water = 4.2kJ/kg/k and density of water = 1g/cm3.
Calculate the:
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(ii) Mass of ethane burnt (RFM of ethane = 30).
Date posted: September 12, 2019. Answers (1)
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Use the thermo chemical equations below to answer the questions that follow.
(i) Name two types of heat changes represent by 
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Date posted: September 12, 2019. Answers (1)
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Study the following part of periodic table chart and use it to answer the question that follow. The letters are of the actual symbols of the elements.
(i) Which elements form ions with charge of -2. Explain.
(ii) Compare the ionic radius of C and E. Explain.
(iii) Write the formular of the compound formed between element G and H.
(iv) In terms of structure of bonding, explain why the oxides of D has a lower melting point than that of G.
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Date posted: September 12, 2019. Answers (1)
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Date posted: September 12, 2019. Answers (1)
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The table below gives the solubilities of potassium nitrate at different temperatures.
(i) Plot a graph of the solubility of potassium nitrate (vertical axis) against temperature.
(ii) Using the graph:
I. Determine the solubility of potassium nitrate at 150C.
II. Determine the mass of potassium nitrate that remained undissolved given that 80g of potassium nitrate were added to 100cm3 of water and warmed to 400C. (2mks)
(iii) Determine the molar concentration of potassium nitrate at 1500C. (Assume there is no change in density of water at this
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Date posted: September 12, 2019. Answers (1)
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Date posted: September 12, 2019. Answers (1)
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(i) Which element is likely to be hydrogen? Give a reason for your answer.
(ii) What is the 
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(iii) In the space provided, draw a labeled diagram of the electrochemical cell that would be obtained when half-cells of element B and D are combined.
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Date posted: September 12, 2019. Answers (1)
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Date posted: September 12, 2019. Answers (1)
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Calculate the relative...(Solved)
When 0.1g of a certain compound Q was burned and used to heat 150cm3 of water, the temperature rose from 250C to 290C.
Calculate the relative molecular mass of the compound given that 1 mole of the compound has an enthalpy of -1072kJ/mol.
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Date posted: September 12, 2019. Answers (1)
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(i) At what temperature does the water boil?
(ii) Giving reason(s) is this pure or impure water?
(iii) State the effect of impurities on the boiling point of water?
Date posted: September 12, 2019. Answers (1)