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This is one of our many quizzes on Alkanes. Click on this to access more such competitive quizzes on Organic Chemistry.

Alkanes Quiz 2

chemistry

 Prem was working on the question of IUPAC naming of the branched-chain of alkanes. What will be the correct answer for the given structure? $ \\ $<img  src="https://cmds-vedantu.s3.ap-southeast-1.amazonaws.com/prod/question-sets/fcabf9ba-cc80-4524-b7c0-f156e8449b19418729073347814187.png"/>

 Identify the longest carbon chain and the substituents attached to it.

  The given structure has the IUPAC name 5-ethyl-3-methyl octane. As the longest parent chain is octane, which has eight C atoms and two substituents attached in the fifth and third position. In the third position, a methyl group, and in the fifth position, an ethyl group is attached.

  Arun burnt propane in the presence of excess oxygen, which type of reaction was it, what will be the products obtained?

  Propane is a hydrocarbon, which is an alkane.

 The burning of propane $($or say any alkane$)$ is a complete combustion reaction since the combustion is complete and all the alkane converts to water and carbon dioxide.

  How many H atoms will be present in the eighth analogue member of the cycloalkane series?

  The general formula of cycloalkane is ${{C}_{n}}{{H}_{2n}}$.

 There will be 16 H atoms since the eighth analogue member of the cycloalkane series is octane which has the molecular formula, ${{C}_{8}}{{H}_{16}}$.

  Tipu had four test tubes of bromine water and she added four samples to each test tube. She observed that except one all the other three bromine solutions turned colorless from brown color. Which was the sample that retained the color?

 The bromine water test is a qualitative test for unsaturation.

The bromine solution test is a detection test for unsaturation. When molecules with the double or triple bond are added to bromine water the color gets discolored whereas the alkanes will retain the brown color.

 Through which method could we synthesize a higher alkane from an alkyl halide?

The reaction in which higher alkane is prepared from alkyl halide is the Wurtz reaction. In this reaction, two moles of alkane react with $Na$ in the presence of dry ether, undergoing a coupling reaction, and forming a higher alkane. $ \\ $ Ex: Bromoethane to butane: $2{{C}_{2}}{{H}_{5}}+Na\to {{C}_{2}}{{H}_{5}}-{{C}_{2}}{{H}_{5}}$