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(i) Condenser
(ii) To indicate when a liquid is boiling, a thermometer reads a constant temperature
(iii) A
(iv) Ethanol
Reason:- It has a lower boiling of 78oC compared to water with a boiling point of 100oC
or - The liquid with the lower boiling point boils first and its vapours are condensed
and the condenser to be collected as the first distillate
(v) Fractional distillation
(vi) - To separate components of crude oil
- To isolate O2 and N2 from air
- To manufacture spirits
(vii)- They are immiscible liquids
- They have different but close boiling points
maurice.mutuku answered the question on October 11, 2019 at 09:41
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Date posted: October 11, 2019. Answers (1)
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Classify the following processes as chemical changes or physical changes
Process physical or chemical
Neutralization ………………………………………
Sublimation ………………………………………
Fractional distillation ………………………………………..
Displacement reaction …………………………………………
Date posted: October 11, 2019. Answers (1)
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The apparatus below were used by a student to study the effect of heat on hydrated copper II sulphate
(a) What is the role of the ice cold water
(b) Name liquid P
(c) What observation is made in the boiling tube
Date posted: October 11, 2019. Answers (1)
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(i) Identify the method above.
(ii) Give one of its disadvantages
(iii) Name a mixture which can be separated by the set-up above
Date posted: October 11, 2019. Answers (1)
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(i) What evidence is then to support the statement...(Solved)
Cooking oils comprise of a mixture of compounds which have a boiling point range
of 23oC to 27oC.
(i) What evidence is there to support the statement that cooking oil is a mixture?
(ii)Name another experimental technique that could be used to confirm your answer in part (i) above
Date posted: October 11, 2019. Answers (1)
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Date posted: October 11, 2019. Answers (1)
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The two elements P and R were separately burned in air, the products gave the results recorded in the table below:
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(b) Describe how the nature of the solutions of the of the oxides were determined
Date posted: October 11, 2019. Answers (1)
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Explain(Solved)
It is advisable to set a Bunsen burner to luminous flame prior to an experiment.
Explain
Date posted: October 11, 2019. Answers (1)
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questions that follow:(Solved)
The diagram below shows the heating curve of a pure substance. Study it and answer the
questions that follow:
(a) What physical changes are taking place at points X and Z?
(b)Explain what happens to the melting point of sodium chloride added to this substance
Date posted: October 11, 2019. Answers (1)
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(Letters given are not real symbols)(Solved)
Study the information in the table below and answer questions that follow.
(Letters given are not real symbols)
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Date posted: October 11, 2019. Answers (1)
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Date posted: October 11, 2019. Answers (1)
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Date posted: October 11, 2019. Answers (1)
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State the identity of;
(i) P
(ii) W
Date posted: October 11, 2019. Answers (1)
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Explain
Date posted: October 11, 2019. Answers (1)
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The diagram below gives the observations that were made(Solved)
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The diagram below gives the observations that were made
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Date posted: October 11, 2019. Answers (1)
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The set-up below shows the products formed when solid lead (ii) nitrate is heated.
a) Identify:
(i) Liquid X
(ii) Gas Y
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Date posted: October 1, 2019. Answers (1)