(a) (i) Particles gaining kinetic energy, temperature increasing.
(ii) Particles rearranging themselves as they change from liquid to gas and all the heat supplied used for this rearrangement and no temperature rise occurs.
(b) Melting point of naphthalein.
sharon kalunda answered the question on March 29, 2019 at 09:43
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3.22g of hydrated sodium sulphate, Na2SO4.XH2O were heated to a constant mass of 1.42g. Determine the value of X in the formula. (Na = 23.0, S = 32.0, O = 16.0, H = 1).
Date posted: March 29, 2019. Answers (1)
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(c) At which electrode does reduction occurs.
Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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(b) Which dye is pure?
(c) Indicate on the diagram the solvent front.
Date posted: March 29, 2019. Answers (1)
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(a) Write an ionic equation for the reaction between lead nitrate and sodium sulphate solutions.
(b) Determine the mass of lead salt formed in (a) above (Pb = 207, S = 32, O = 16).
Date posted: March 29, 2019. Answers (1)
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(a) State...(Solved)
A dry cell is constructed using the following substances. Zinc metal, graphite rod, ammonium chloride paste and manganese (IV) oxide mixed with carbon powder.
(a) State the roles of:
(i) Ammonium chloride paste.
(ii) Manganese (IV) oxide mixed with carbon powder.
(b) Given that:
Calculate the e m f of the cell given zinc forms the negative electrode.
Date posted: March 29, 2019. Answers (1)
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Dry hydrogen chloride gas was passed over heated iron wool as shown below.
(a) State the observation made in the combustion tube at the end of the experiment.
(b) Write the equation for the reaction taking place:-
(i) In the combustion tube.
(ii) Leading to production of the blue flame.
Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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The diagram below is a set-up of apparatus used to react ammonia gas with iron (IV) chloride solution.
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(b) Explain why the funnel is used to deliver the ammonia into the solution.
Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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Study the table below and use it to answer the questions that follow.
(i) In which of the solution will phenolphthalein indicator be colourless.
(ii) Which of the solutions could be used to relieve heartburn? Explain.
Date posted: March 29, 2019. Answers (1)
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(b) Write the formula of the complex ion present in the colourless solution Q.
Date posted: March 29, 2019. Answers (1)
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Date posted: March 29, 2019. Answers (1)
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Complete the table below to show the effect of different factors on the position of equilibrium.
Date posted: March 29, 2019. Answers (1)
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In the down’s process (used for extraction of sodium) a certain salt is added to lower the melting point of sodium chloride from 8000C to about 6000C.
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(ii) Why is it necessary to lower the temperature?
(iii) Give one use of sodium.
Date posted: March 29, 2019. Answers (1)
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The set-up below shows how gas A was prepared and reacted with heated magnesium.
(a) Give a reason why it is not advisable to heat magnesium before heating ammonium nitrite.
(b) (i) Identify gas A.
(ii) Write a chemical equation for the reaction between gas A and magnesium.
Date posted: March 29, 2019. Answers (1)
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(a) What is the molecular formular of this compound?
(b) To which...(Solved)
The empirical formula of a compound is CH2 and its molecular mass is 42.
(a) What is the molecular formular of this compound?
(b) To which group of hydrocarbons does the compound above belong?
(c) Draw the structural formula of the fourth member of this series and give its IUPAC name.
Date posted: March 29, 2019. Answers (1)