a) A candle wax is mainly a compound consisting of two elements. Name the two elements b) The set-up below was used to investigate the burning of a candle. Study it and answer the questions that follow.

a) A candle wax is mainly a compound consisting of two elements. Name the two elements
b) The set-up below was used to investigate the burning of a candle. Study it and answer the questions that follow.

i) What would happen to the burning candle if the pump was turned off?
ii) State and explain the changes that are likely to occur in tube N by the end of the experiment.
iii) Name two gases that come out through tube M.
iv) What is the purpose of calcium chloride in tube L?
v) Name another substance that could be used in the place of calcium oxide in tube N.

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a)i) Hydrogen.

ii) Carbon

b) i) It extinguishing because carbon (IV) oxide will accumulate around it putting it off.

ii) Mass increase since water vapour reacts with calcium oxide (Cao) and forms calcium hydroxide (Ca(OH)₂), which then reacts with carbon (IV) oxide (CO₂) to produce calcium carbonate (CaCO₃) and so the mass increases.

iii) Nitrogen, Helium, Neon, argon;

iv) It absorbs moisture which is produced from burning candle.

v) Sodium hydroxide

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johnmulu answered the question on April 7, 2017 at 08:36

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