Burning involves use of oxygen hence the products include the mass of candle and oxygen
johnmulu answered the question on February 2, 2017 at 07:09
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A candle wax is mainly a compound consisting of two elements. Name the two elements
Date posted: February 2, 2017. Answers (1)
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In an experiment, a piece of magnesium ribbon was cleaned with steel wool. 2.4 g of the clean magnesium ribbon was placed in a crucible and completely burnt in oxygen. After cooling, the product weighed 4.0 g
a) Explain why it was necessary to clean the magnesium ribbon
b) What observation was made in the magnesium ribbon
c) Why was there an increase in mass
Date posted: February 2, 2017. Answers (1)
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When wood is burnt, a grey powder called ash remains. The ash is stirred with water and filtered a colourless solution is obtained
a) What is the main component of the colourless solution
b) Explain your answer in (a) above
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Date posted: February 2, 2017. Answers (1)
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Date posted: February 2, 2017. Answers (1)
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Date posted: February 2, 2017. Answers (1)
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Date posted: February 2, 2017. Answers (1)
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Date posted: February 2, 2017. Answers (1)
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Date posted: February 2, 2017. Answers (1)
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ii) The solution can be shown to be an indicator
Date posted: February 2, 2017. Answers (1)
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Date posted: February 2, 2017. Answers (1)
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Date posted: February 2, 2017. Answers (1)
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10g of sodium hydrogen carbonate were dissolved in 20 cm3 of water in a boiling tube. Lemon juice was then added dropwise with shaking unit there was no further observable change
a) Explain the observation which was made in boiling tube when the reaction was in progress
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Date posted: February 2, 2017. Answers (1)
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Date posted: February 2, 2017. Answers (1)
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Date posted: February 2, 2017. Answers (1)
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Date posted: February 2, 2017. Answers (1)
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When solid A was heated strongly, it gave off water residue. When water was added to the solid residue, the original solid A, was formed
a) What name is given to the process described
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Date posted: February 2, 2017. Answers (1)
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Date posted: February 1, 2017. Answers (1)
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Date posted: February 1, 2017. Answers (1)
- A mixture contains ammonium chloride, copper (II) oxide and sodium chloride. Describe how each of the substances can be obtained from the mixture.(Solved)
A mixture contains ammonium chloride, copper (II) oxide and sodium chloride. Describe how each of the substances can be obtained from the mixture.
Date posted: January 31, 2017. Answers (1)
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Hydrated cobalt (II) chloride exists as pink crystals and anhydrous cobalt (II) chloride is a blue powder. Describe a laboratory experiment that can be used to show that the action of heat on hydrated cobalt (II) chloride is a reversible action.
Date posted: January 31, 2017. Answers (1)