-When aqueous ammonia is added to the water sample dropwise, a white precipitate which dissolves in excess ammonia is formed showing presence of zinc ions
- A few drops of acidified barium nitrate when added forms white precipitate showing presence of sulpate ions.
OR
To the water sample, add 3 drops of ammonia solution until in excess.Formation of a white precipitate that dissolves in excess ammonia solution to form a colourless solution confirms presence of zinc ions.
johnmulu answered the question on February 15, 2017 at 05:36
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A sample of fertilizer is suspected to be calcium ammonium nitrate. Describe chemical test for each of the following ions in the sample
(Solved)
A sample of fertilizer is suspected to be calcium ammonium nitrate. Describe chemical test for each of the following ions in the sample:
a) Calcium ions
b) Ammonium ions.
Date posted:
February 13, 2017
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Answers (1)
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Name two methods that can be used to remove permanent hardness from water
(Solved)
Name two methods that can be used to remove permanent hardness from water.
Date posted:
February 13, 2017
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Answers (1)
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Starting from solid magnesium oxide, describe how a solid sample of magnesium hydroxide can be prepared
(Solved)
a) Starting from solid magnesium oxide, describe how a solid sample of magnesium hydroxide can be prepared.
b) Give one use of magnesium hydroxide.
Date posted:
February 13, 2017
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Answers (1)
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Water from a town in Kenya is suspected to contain chloride ions but not sulphate ions. Describe how the presence of the chloride ions in water can be shown
(Solved)
Water from a town in Kenya is suspected to contain chloride ions but not sulphate ions. Describe how the presence of the chloride ions in water can be shown.
Date posted:
February 13, 2017
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Answers (1)
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Zinc oxide reacts with acids and alkalis (a) Write the equation for the reaction between zinc oxide and...
(Solved)
Zinc oxide reacts with acids and alkalis
a) Write the equation for the reaction between zinc oxide and
i)Dilute sulphuric (VI) acid
ii) Sodium hydroxide solution
Date posted:
February 13, 2017
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Answers (1)
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Starting with aluminium sulphate, describe how solid sample of aluminium hydroxide could be prepared
(Solved)
Starting with aluminium sulphate, describe how solid sample of aluminium hydroxide could be prepared.
Date posted:
February 13, 2017
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Answers (1)
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A student was supplied with a colourless liquid suspected to be water (i) Describe one chemical test that could have been used to show that the liquid was water
(Solved)
A student was supplied with a colourless liquid suspected to be water
i) Describe one chemical test that could have been used to show that the liquid was water
ii) How could it have been shown that the liquid was pure water
Date posted:
February 10, 2017
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Answers (1)
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When solid magnesium carbonate was added to a solution of hydrogen chloride in methylbenzene, there was no apparent reaction
(Solved)
When solid magnesium carbonate was added to a solution of hydrogen chloride in methylbenzene, there was no apparent reaction. On addition of water to the resulting mixture, there was vigorous effervescence. Explain these observations.
Date posted:
February 10, 2017
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Answers (1)
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A bee-keeper found that when stung by a bee, application of a little solution of sodium hydrogen carbonate helped to relieve the irritation from the affected area. Explain
(Solved)
A bee-keeper found that when stung by a bee, application of a little solution of sodium hydrogen carbonate helped to relieve the irritation from the affected area. Explain
Date posted:
February 10, 2017
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Answers (1)
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Give the formula of an oxide which reacts with both dilute hydrochloric acid and hot concentrated sodium hydroxide
(Solved)
a) Give the formula of an oxide which reacts with both dilute hydrochloric acid and hot concentrated sodium hydroxide
b) Give the formulae of the products formed when the oxide in (a) above reacts with excess hot concentrated sodium hydroxide.
Date posted:
February 10, 2017
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Answers (1)
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90 cm3 of 0.01M calcium hydroxide were added to a sample of water containing 0.001 moles of calcium hydrogen carbonate
(Solved)
90 cm3 of 0.01M calcium hydroxide were added to a sample of water containing 0.001 moles of calcium hydrogen carbonate
a) Write an equation for the reaction which took place
b) Calculate the number of moles of calcium ions in 90 cm3 of 0.01M calcium hydroxide.
c) What would be observed if soap solution was added dropwise to a sample of the water after the addition of calcium hydroxide? Give a reason.
Date posted:
February 10, 2017
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Answers (1)
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Write the formula of the complex ion formed in each of the reactions described below
(Solved)
Write the formula of the complex ion formed in each of the reactions described below.
i) Zinc metal dissolves in hot alkaline solution
ii) Copper hydroxide dissolves in excess ammonia solution
Date posted:
February 10, 2017
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Answers (1)
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Give the name of each of the processes described below which takes place when the salts are exposed to air for sometimes
(Solved)
Give the name of each of the processes described below which takes place when the salts are exposed to air for sometimes
i) Anhydrous copper sulphate becomes wet
ii) Magnesium chloride forms an aqueous solution
iii) Fresh crystals of sodium carbonate, Na2CO3.10H2O become covered with white powder of formula Na2CO3.H2O
Date posted:
February 10, 2017
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Answers (1)
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Explain the following observation. A chloride dissolves in water to form an electrolyte while the same chloride dissolves in methylbenzene to form a non-electrolyte
(Solved)
Explain the following observation. A chloride dissolves in water to form an electrolyte while the same chloride dissolves in methylbenzene to form a non-electrolyte
Date posted:
February 10, 2017
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Answers (1)
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During an experiment, chlorine gas was bubbled into a solution of potassium iodide (a) State the observations made
(Solved)
During an experiment, chlorine gas was bubbled into a solution of potassium iodide
a) State the observations made
b) Using an ionic equation, explain why the reaction is redox.
Date posted:
February 10, 2017
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Answers (1)
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State and explain what would happen if a dry red litmus paper was dropped in a gas jar dry chlorine
(Solved)
State and explain what would happen if a dry red litmus paper was dropped in a gas jar dry chlorine.
Date posted:
February 10, 2017
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Answers (1)
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By using only dilute hydrochloric acid, describe how a student would distinguish between barium sulphite from barium sulphate
(Solved)
By using only dilute hydrochloric acid, describe how a student would distinguish between barium sulphite from barium sulphate
Date posted:
February 10, 2017
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Answers (1)
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State and explain what would happen if a dry litmus paper was dropped in a gas jar of chlorine
(Solved)
State and explain what would happen if a dry litmus paper was dropped in a gas jar of chlorine
Date posted:
February 10, 2017
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Answers (1)
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Two reagents that can be used to prepare chlorine gas are manganese (IV) oxide and concentrated hydrochloric acid
(Solved)
Two reagents that can be used to prepare chlorine gas are manganese (IV) oxide and concentrated hydrochloric acid
i) Write an equation for the reaction
ii) Give the formula of another reagent that can be reacted with concentrated hydrochloric acid to produce chlorine gas
iii) Describe how the chlorine gas could be dried in the laboratory
Date posted:
February 10, 2017
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Answers (1)
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State and explain the observations made when excess ammonia gas reacts with chlorine
(Solved)
State and explain the observations made when excess ammonia gas reacts with chlorine
Date posted:
February 10, 2017
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Answers (1)