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Naming of alkanes/alkenes + other questions (1 Viewer)

j12onuzim

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I was wondering how to name some hydrocarbons such as "bromohexane" or "2-3 bromopentane" or "cyclohexane" are named and how are these different from normal hydrocarbons? How are they named?

Also, how do you go about with the structural formulas? They seem to confuse me,especially the benzyl ring. Could someone please explain to me what the benzyl ring is, its purposes e.t.c.?

I am terrible at chemistry.

Thanks
 

Prawnchip

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Go on youtube and watch ausetute. They helped me a lot with naming :)
 

Talia95

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A benzene ring is simply 6 carbons joined in a hexagon shape, with a hydrogen at each carbon point. When it's in alkanes, like styrene, its just attached to the normal carbon chain. In things like styrene, it is a big, stiff group, and helps make the styrene stiff and hard.
 

Dementured

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I was wondering how to name some hydrocarbons such as "bromohexane" or "2-3 bromopentane" or "cyclohexane" are named and how are these different from normal hydrocarbons? How are they named?

Also, how do you go about with the structural formulas? They seem to confuse me,especially the benzyl ring. Could someone please explain to me what the benzyl ring is, its purposes e.t.c.?

I am terrible at chemistry.

Thanks
Bromohexane is hexane with a bromine on it, but nothing is named bromohexane. A hydrocarbon named 2,3-dibromopentane means that there are two bromines on the 5-carbon hydrocarbon structure at the 2nd and 3rd carbon.
 

anomalousdecay

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You do not need to know the structure of benzene or about the benzyl rings.
It would probably be necessary to learn the structure of cyclohexene and cyclohexane for the bromine water experiment (I just used hex-1-ene and hexane instead).

When naming hydrocarbons, alphabetical order is first priority.
Also, you are better off getting into the habit of writing the number in the text as this is IUPAC preferred.
Example- hexan-2-ol NOT 2-hexanol, except when you have di/tri, etc.

By the way, 2-3 bromopentane is wrong. It should be 2,3-dibromopentane.

For structural formulas, you must know how to draw and name a compound.

First, look at the how many non-hydrogen atoms are in the name....is there a di? are there fluoro or chloro in the name? etc.
Look at the carbon number assigned to each atom. Then link the atom to the chain.

Hope this helps.
 

someth1ng

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You do not need to know the structure of benzene or about the benzyl rings.
It would probably be necessary to learn the structure of cyclohexene and cyclohexane for the bromine water experiment (I just used hex-1-ene and hexane instead).

When naming hydrocarbons, alphabetical order is first priority.
Also, you are better off getting into the habit of writing the number in the text as this is IUPAC preferred.
Example- hexan-2-ol NOT 2-hexanol, except when you have di/tri, etc.

By the way, 2-3 bromopentane is wrong. It should be 2,3-dibromopentane.

For structural formulas, you must know how to draw and name a compound.

First, look at the how many non-hydrogen atoms are in the name....is there a di? are there fluoro or chloro in the name? etc.
Look at the carbon number assigned to each atom. Then link the atom to the chain.

Hope this helps.
Both are perfectly acceptable.
 

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