(a) J is basic
Bases turn litmus blue and methyl orange yellow
(b) Water, NaCl (any neutral substance)
marto answered the question on October 1, 2019 at 08:01
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State with reasons whether the changes below are physical or chemical.
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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The flow chart below illustrates two industrial processes, Haber process and the Contact process:
(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
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(g) Give one major use of compound D
Date posted: October 1, 2019. Answers (1)
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Study the set-up below and answer the questions that follow.
a) (i) Name Gas X
(ii) State the effect of releasing gas X to the environment
b) Write down equations for the reactions taking place in;
(i) Tube I
(ii) Tube II
(iii) Flask
c) State the observation made in tube III
d) Write down an equation for the reaction which could be used to generate Carbon (IV) Oxide for the above set up
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Date posted: October 1, 2019. Answers (1)
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a) How do the atomic radius of element
(i) X and M compare. Explain.
(ii) U and Q. Explain
b) Which letter represent the most reactive metal. Explain.
Date posted: October 1, 2019. Answers (1)
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The number of protons, neutrons and electrons in atoms A to F are given in the table below the letters do not represent the actual symbol of the elements:-
Choose from the table the letters that represent:
(i) An atom of a metal
(ii) A neutral atom of a non-metal
(iii) An atom of a noble gas
(iv) A pair of isotopes
(v) A cation
(vi) Anion
Date posted: October 1, 2019. Answers (1)
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Date posted: October 1, 2019. Answers (1)
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(i) Write an equation for the reaction
(ii) State two precautions that must be taken before the combustion begins...(Solved)
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(i) Write an equation for the reaction
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Date posted: October 1, 2019. Answers (1)
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a) Write an equation for the reaction.
b) Name an appropriate drying agent for hydrogen gas.
c)...(Solved)
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a) Write an equation for the reaction.
b) Name an appropriate drying agent for hydrogen gas.
c) Explain why copper metal cannot be used to prepare hydrogen gas.
Date posted: October 1, 2019. Answers (1)
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Date posted: September 27, 2019. Answers (1)
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Date posted: September 26, 2019. Answers (1)
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i) Name Compound T
ii) Gas U
iii) The equation below shows the reaction between sulphur (IV) oxide gas and oxygen gas to produce sulphur (VI) oxide in contact process.
2 SO2(g) + O2(g)----->2SO3 D = -197 kJ/mol
State two conditions that are necessary for maximum production of SO3.
iv) Name the catalyst used for this reaction.
Date posted: September 26, 2019. Answers (1)
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Study the reaction scheme below and use it to answer the questions that follow.
i) Name the process in;
Step I
Step II
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Step II
Step III
iii) Name the type of reaction taking place in step III
Date posted: September 26, 2019. Answers (1)
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i) State the colour change.
ii) Explain why castor...(Solved)
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i) State the colour change.
ii) Explain why castor oil reacts with acidified Potassium manganate (VII) to cause the colour change.
Date posted: September 26, 2019. Answers (1)
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Date posted: September 25, 2019. Answers (1)
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i) What is the name of the process by which the constituents of crude oil can be separated?
ii) Give one use of the gases component.
iii) Give the order by which the components are obtained from the mixture, starting with the first.
Date posted: September 25, 2019. Answers (1)
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iii) State with a reason the least soluble dye in the moving solvent.
Date posted: September 25, 2019. Answers (1)
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The table below shows the results obtained when four solvents were used to separate a dye. Study the results and use them to answer the questions that follow.
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Date posted: September 25, 2019. Answers (1)
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Date posted: September 25, 2019. Answers (1)