i) K – potassium
ii) Cl – chlorine
iii) Fe – iron
iv) Mg – magnesium.
v) C – carbon
vi) Be – beryllium.
marto answered the question on October 1, 2019 at 09:12
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Date posted: October 1, 2019. Answers (1)
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a) Determine the melting point of solid X.
b) After the experiment the student concluded that substance x was pure substance. Explain why he concluded so.
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Date posted: October 1, 2019. Answers (1)
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iv) Aluminium nitrate(Solved)
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i) Magnesium oxide.
ii) Zinc chloride
iii) Sodium sulphate.
iv) Aluminium nitrate
Date posted: October 1, 2019. Answers (1)
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Study the diagram below and answer the question that follows.
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b) Draw a similar diagram to show the effect of temperature on solid carbon (IV) oxide (dry ice)
Date posted: October 1, 2019. Answers (1)
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Date posted: October 1, 2019. Answers (1)
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Date posted: October 1, 2019. Answers (1)
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(i) Atom
(ii) Mass number(Solved)
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(i) Atom
(ii) Mass number
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Date posted: October 1, 2019. Answers (1)
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(a) Name the two oxides
(b) State the nature of the solution when the above mentioned oxides are...(Solved)
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Date posted: October 1, 2019. Answers (1)
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(ii) State how soot is formed from hydrocarbons(Solved)
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Date posted: October 1, 2019. Answers (1)
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Date posted: October 1, 2019. Answers (1)
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Date posted: October 1, 2019. Answers (1)
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Oxygen is obtained on large scale by the fractional distillation of air as shown on the flow chart below.
a) Explain why air is considered as a mixture
b) Identify the substance that is removed at the filtration stage
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Date posted: October 1, 2019. Answers (1)
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(a)...(Solved)
In temperate countries, salt is sprayed on roads to defrost and clear roads but the long term effect on this practice is costly to motorist.
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Date posted: October 1, 2019. Answers (1)
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Date posted: October 1, 2019. Answers (1)
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A student set-up the apparatus below in order to determine the percentage by volume of oxygen in air.
a) Why did water rise when the reaction had stopped?
b) The student wrote the expression for the percentage by volume of oxygen in air as
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Date posted: October 1, 2019. Answers (1)
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Blue litmus remained blue in both solutions. Methyl orange remained...(Solved)
Two solutions J and K were tested with blue litmus papers and methyl orange indicator.
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(b) Give an example of a substance that K is likely to be.
Date posted: October 1, 2019. Answers (1)
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Date posted: October 1, 2019. Answers (1)
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Date posted: October 1, 2019. Answers (1)
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Date posted: October 1, 2019. Answers (1)
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(a) (i) Give the name of the process by which air is seperated into oxygen and nitrogen
(i) Apart from oxygen and nitrogen gases produced from process (a)(i) name one other gas produced
(b) Name the substances represented by the letters A, B, C and D
(c) Name the catalysts used in:
(i) Haber Process
(ii) Contact Process
(d) Explain the role of the catalysts in both the Haber and the Contact processes
(e) Write a chemical equation for the formation of compound B
(f) Calculate the percentage by mass of the nitrogen present in compound D
(g) Give one major use of compound D
Date posted: October 1, 2019. Answers (1)