Correct Answer - Option 4 : Yellow
Explanation:
Sooty flame:
- The unsaturated hydrocarbons like alkenes, alkynes are aromatic hydrocarbons that partially burned with a yellow sooty flame.
- It is due to the incomplete combustion of the hydrocarbon in air.
- A large amount of carbon does not completely oxidize in the air and gives sooty flame.
Non-Sooty flame:
- The saturated hydrocarbons burn with a Blue colour non-sooty flame.
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Alkanes are saturated hydrocarbons and classified as a type of aliphatic hydrocarbon.
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Hexane is a type of Alkanes that burns with a blue non-sooty flame. Hence option 2 is correct.
- The blue flame emerges when the complete combustion of carbon takes place.
Hydrocarbons are the derivates of the carbon and hydrogen compounds. In organic chemistry, Hydrocarbons are classified into three:-
- Alkanes
- Alkenes
- Alkynes
1. Alkanes: These are represented by Single Bond between two carbons.
- The chemical formula CnH2n+2
- the first member of the alkane group - Methane (CH4)
- Symbolic representation of alkanes is —C—C—
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Methane is colorless, odorless, flammable gas. it is used primarily as fuel to make heat and light. it is used in the manufacturing of organic chemicals.
2. Alkenes: These are represented by Double Bond between two carbons
- The chemical formula CnH2n
- The first member of the alkene group - Ethene (C2H4)
- Symbolic Representation of alkenes is —C=C—
- Ethene is used in the production of ethylene glycol ( 1,2-ethanediol ) an automotive anti-freezing agent, used in the production of polymers such as polythene, polyvinyl chloride, polystyrene.
3. Alkynes: These are represented by a Triple Bond between two carbons
- The chemical formula CnH2n-2
- The first member of the alkyne group - Ethyne (C2H2)
- Symbolic representation of alkynes is —C=C—
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Ethyne is also called Acetylene which is used in portable lighting, welding, and cutting, production of Chemicals.
