The end products of burning a candle in the atmosphere are water and

Analysis

The question asks for the products formed when a candle burns in the atmosphere. A candle is primarily made of paraffin wax, which is a hydrocarbon (a compound consisting of carbon and hydrogen).

Concept

Combustion is a chemical reaction between a substance (the fuel) and oxygen. When a hydrocarbon burns completely in the presence of sufficient oxygen (as found in the atmosphere), it undergoes complete combustion.

The general word equation for the complete combustion of a hydrocarbon is: Hydrocarbon + Oxygen → Carbon (IV) Oxide + Water

• Carbon (IV) Oxide ($CO_2$): Produced from the oxidation of the carbon atoms in the wax.
• Water ($H_2O$): Produced from the oxidation of the hydrogen atoms in the wax.

Step-by-Step Solution

1. Identify the fuel: A candle is a hydrocarbon ($C_nH_{2n+2}$).
2. Identify the reactant: The candle burns in the atmosphere, which contains oxygen ($O_2$).
3. Determine the reaction type: Burning in the atmosphere implies an excess of oxygen, leading to complete combustion.
4. Analyze the products: • The carbon in the wax reacts with oxygen to form Carbon (IV) oxide ($CO_2$). • The hydrogen in the wax reacts with oxygen to form Water ($H_2O$).
5. Evaluate the options: • A: Carbon (II) oxide ($CO$) is a product of incomplete combustion (usually when oxygen is limited). • B & D: Sulphur oxides are produced only if the fuel contains sulphur impurities, which is not the primary reaction for a candle. • C: Carbon (IV) oxide ($CO_2$) is the correct product of complete combustion.

Conclusion

The complete combustion of the hydrocarbon wax in a candle yields water and carbon (IV) oxide.

Exam Tip: Remember that "Carbon (IV) oxide" is the IUPAC name for Carbon dioxide ($CO_2$). Always look for the "complete combustion" products ($CO_2$ and $H_2O$) when dealing with hydrocarbons in exam questions.