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A mixture contains iron(III)chloride,zinc(II)oxide and potassium chloride. Describe how each of the substance can be obtained from the mixture.
Date posted:
April 23, 2018
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Substance Q has a melting point of 15°C and boiling point of 70°c.
(a)On the same axis,draw the melting point and boiling point graph for Q and the room temperature.
(b)State the physical state of substance Q at room temperature.
Date posted:
April 22, 2018
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Explain why ammonium trioxocarbonate (iv) leaves no residue when heated
Date posted:
April 22, 2018
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Write chemical equation for reaction between dry hydrogen gas and heated lead (ii) oxide.
Date posted:
April 21, 2018
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Given the following reagents describe how to prepare lead (ii) sulphate: Solid potassium sulphate, solid lead (ii) carbonate, dilute nitric (iv) acid and distilled water.
Date posted:
April 19, 2018
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What are the advantages of universal indicators over other acid-base indicators?
Date posted:
April 19, 2018
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A crystal of copper (II) sulphate was placed in a beaker of water. The beaker was left standing for two days without shaking. State and explain the observations that were made.
Date posted:
April 17, 2018
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Explain how the hotness of a bunsen burner flame can be increased.
Date posted:
April 17, 2018
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Explain why it is not advisable to store a solution of cadmium nitrate in a container made of zinc.
Date posted:
April 17, 2018
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Dry ammonia gas is passed over heated lead(II) oxide in a combustion tube.
a) What observation would be made in the combustion tube
b) Outline a chemical test you would use to identify the colourless liquid collected in the u-tube
c) Name the colourless liquid
d) Write an equation for the reaction between ammonia and lead(II)oxide
Date posted:
April 17, 2018
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Name the method that can be used to obtain pure iron (III) chloride from a mixture of iron (III) chloride and sodium chloride.
Date posted:
April 14, 2018
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Calculate the number of moles of molecules in 7.30g of HCL
Date posted:
April 12, 2018
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Lead chloride is an insoluble salt so it is prepared by double decomposition. So basically we must come up with a soluble salt from the lead oxide, the mix it with another soluble chloride to form the lead chloride.
Date posted:
April 12, 2018
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Starting with lead(ii)oxide, describe how you would prepare a solid sample of lead (ii)chloride.
Date posted:
April 11, 2018
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Fraction distillation of liquid air usually produces nitrogen and oxygen as the major products
1. Name one substance that is used to remove carbon dioxide from the air before it is changed into liquid
2. Describe how nitrogen gas is obtained from the liquid air (boiling points nitrogen = -196 degrees oxygen =-183 degrees
Date posted:
April 10, 2018
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Explain how you would separate a mixture of nitrogen and oxygen given that their boiling points are -196^0c and 183^0c.
Date posted:
April 10, 2018
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Carbon and silicon belong to the same group of the periodic table yet carbon (4) oxide is a solid with a high melting point. Explain this difference
Date posted:
April 6, 2018
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Deals with separation of mixtures under fractional distillation
Date posted:
March 13, 2018
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Outline the physical properties of carbon (iv) oxide
Date posted:
February 28, 2018
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State the uses of carbon (ii) oxide.
Date posted:
February 28, 2018
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Outline the physical properties of carbon (ii) oxide
Date posted:
February 28, 2018
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Starting with aqueous magnesium sulphate, describe how you would obtain a sample of magnesium oxide
Date posted:
February 28, 2018
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How would you separate a solid mixture of lead II chloride and copper II oxide?
Date posted:
February 27, 2018
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A solution of ammonia in methyl benzene has no effect on red litmus paper while a solution of ammonia in water has. Explain this.
Date posted:
February 26, 2018
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What are chemical properties of hydrogen gas?
Date posted:
February 17, 2018
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What are the sources of heat in laboratory?
Date posted:
January 8, 2018
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A hydrated salt has the following composition by mass. Iron 20.2%, Oxygen 23.0%, Sulphur 11.5%, Water 45.3%. Its relative formula mass is 278. Determine the formula of hydrated salt
Date posted:
December 31, 2017
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Which is the best method to separate sodium chloride from a solution of potassium chloride and sodium chloride mixture?
Date posted:
December 30, 2017
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State and explain what is observed when a burning piece of magnesium is lowered into a gas jar containing dry chlorine gas
Date posted:
December 26, 2017
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Give the observations made when lead (ii)nitrate is heated strongly and write a balanced chemical equations to show the action
Date posted:
December 21, 2017