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