(a) Colour of copper (II) Oxide changes from black to brown
(b) (i) Nitrogen /N2(g)
(ii) Water/H2O(l)
maurice.mutuku answered the question on October 24, 2019 at 05:45
- When dry ammonia gas is passed over hot copper (II) Oxide, a shinny brown residue and a colourless droplets are formed. Explain these two observations(Solved)
When dry ammonia gas is passed over hot copper (II) Oxide, a shinny brown residue and a colourless droplets are formed. Explain these two observations
Date posted: October 24, 2019. Answers (1)
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Date posted: October 24, 2019. Answers (1)
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When a few drops of aqueous ammonia were added to a colourless solution X, a white precipitate was formed. On addition of more aqueous ammonia, the white precipitate dissolved to a colourless solution Q
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(c) Write an ionic equation for the formation of the white precipitate
Date posted: October 24, 2019. Answers (1)
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At 113oC it melts into light brown liquid. The liquid then darkens to...(Solved)
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At 113oC it melts into light brown liquid. The liquid then darkens to become reddish-brown
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b) Write a chemical equation for the reaction that took place in the combustion tube
c) State one use of gas P
Date posted: October 24, 2019. Answers (1)
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The diagram below represents an in complete set-up for preparation of a dry sample of gas R
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b) Write a chemical equation for the reaction that produces gas R
Date posted: October 22, 2019. Answers (1)
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(i) What is the purpose of the filter funnel in the set-up above?
(ii) What would happen if a delivery tube was used in place of the filter funnel?
(iii) What observation would be made on litmus paper placed into the solution in the beaker at the end of the experiment?
Date posted: October 22, 2019. Answers (1)
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(ii) Write an equation for the formation of gas X
(iii) What precaution should be observed when preparing gas X by the above method?
(iv) Describe the suitable drying agent for gas X
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(vi) State two physical properties of gas X
Date posted: October 22, 2019. Answers (1)
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(a) What is the purpose of the sodium hydroxide?
(b) Write an equation for the reaction taking place in chamber II
(c) The nitrogen gas obtained is not pure. Explain
Date posted: October 22, 2019. Answers (1)
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The final concentration of the acid was found to be 0.1M. Give...(Solved)
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Date posted: October 22, 2019. Answers (1)
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(i) Solution A
(ii) Solution B
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Date posted: October 22, 2019. Answers (1)
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(a) Name gas X
(b) State one physical property which makes it possible for the gas to be collected as shown
(c) State one commercial use of gas X
Date posted: October 22, 2019. Answers (1)
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Date posted: October 22, 2019. Answers (1)
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A student wanted to prepare a sample of ammonia...(Solved)
Ammonia gas is prepared in the laboratory by the action of an alkali on an ammonium salt.
A student wanted to prepare a sample of ammonia gas in the laboratory.
(a) Give one alkali that can be used in the above experiment
(b) Write an equation for the reaction that takes place in the above experiment
Date posted: October 22, 2019. Answers (1)
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(b) State and explain two observations made inside the conical flask
Date posted: October 22, 2019. Answers (1)
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Date posted: October 22, 2019. Answers (1)
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Date posted: October 22, 2019. Answers (1)
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(i) 2.63g of a solution of sodium chloride at 20.0oC was reacted with silver nitrate. After filtration,washing and drying, 2.36g of silver chloride was obtained. Determine the solubility of sodium
chloride at 20.0oC . (Na=23, Cl= 35.5, Ag = 108)
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Date posted: October 22, 2019. Answers (1)