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Is CH3CH2CH2CH(CH3)2 a primary, secondary or tertiary carbon and why?

I just started Chem and I am having a hard time getting started.


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Dr. Chandrani M. | I am Organic Chemistry Teacher and Your Science TeacherI am Organic Chemistry Teacher and Your ...

Both CH2 (2nd CH2 and 3rd CH2 from left) Has Secondary Carbon atom

There is only 1 CH  and this carbon is Tertiary

All the CH3 Carbons are Primary Carbon atom (1st CH3 and last 2 CH3)


Michael B. | Seasoned and experienced tutor with extensive science backgroundSeasoned and experienced tutor with exte...

Just to chime in, the atom designation increases with the amount of carbon atom bonding.

A primary carbon has one carbon atom bonded to it.

A secondary carbon atom has two carbon atoms bonded to it.

A tertiary carbon atom has three carbon atoms bonded to it.

A quaternary carbon atom has four carbon atoms bonded to it.

Arthur S. | Math, Science, Chemistry, and Computer TutorMath, Science, Chemistry, and Computer T...

First you must look for the longest chain of carbons to correctly determine the configuration. That is five carbons with a methyl group on number 4 so the second methylene group is attached to two other carbons and therefore secondary.

There is one tertiary carbon and the primary carbons are 1, 5 and the methyl group attached to 4.


George C. | Humboldt State and Georgetown graduateHumboldt State and Georgetown graduate
5.0 5.0 (2 lesson ratings) (2)

Ambiguous.  Which carbon are you talking about in this pentane molecule?  There are examples of each here, but which is unclear.

There are 3 1°, 2 2º, and 1 3º carbon here.

Elizabeth D. | Science, Math, and How to Write about ThemScience, Math, and How to Write about Th...
5.0 5.0 (4 lesson ratings) (4)

Primary (1º) is a carbon with three hydrogens on it.

Secondary (2º) is a carbon with two hydrogens on it.

Tertiary (3º) is a carbon with only one hydrogen on it.