h3c ch ch ch2 ch2 ch3        ch3  ch3  h3c ch2 ch=ch ch2 ch2 ch3                               ch3 ch3 ch3 ch2 ch2 ch2 ch2 ch ch2  Name the compounds.

4 Answers

bandmanjoe's profile pic

bandmanjoe | Middle School Teacher | (Level 2) Senior Educator

Posted on

All these compounds are substances called hydrocarbons.  They are called such because carbon and hydrogen are the two chief elements in their molecular makeup.  There is an entire branch of chemistry called organic chemistry that studies the structure and properties of hydrocarbon substances.  Hydrocarbons are named for the number of carbon atoms in their primary chain, sometimes called the 'backbone" of the molecule.  Any other structures are indicated by their location on the specific number of whatever carbon atom they are attached to.

So, that being said, here we go:  compound #1 has a backbone of six carbon atoms, making it a hexane.  It also has two methane groups. on the second and third carbons.  We would correctly refer to these as methyl groups and indicate what number carbon they are attached to, so the correct name for this compound is 2,3-dimethylhexane.  Compound #2 has a double bond between carbons 3 and 4, making it an alkene.  It has 7 carbon atoms, so we would simply indicate the location of the double bond and call it 3-heptene.  Compound #3, I am assuming the lone CH3 is misplaced and should be directly above the next-to-last carbon (CH), which would make sense.  The two CH3 groups I am hoping is a misprint as well, the second one should be a CH2.  This one we would indicate the location of the lone methyl group, which would be on carbon number 2 (always count for the lowest number).  The name of the compound 2-methyloctane.

jerichorayel's profile pic

jerichorayel | College Teacher | (Level 2) Senior Educator

Posted on

to understand the naming of the following coumpounds that you had, always remember that we should always have to take in the consideration to :

1. locate the longest chain

2. the location of the substituents

3. types of the substituesnts

4. priority rules


1. 2,3 dimethylhexane (2 and 3 stand for the methyl group which was attached to the parent chain which is hexane. apparently it was a "di" because there are two methyl groups attached.)

2. hept-3-ene OR 3-heptene (the double bond is in the third carbon).

3. 2-methyloctane (the methyl group is on the second carbon. we cannot name this as 7-methylloctane because we prioritize the smaller value which is 2 for 2-methyloctane)

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chaobas's profile pic

chaobas | College Teacher | (Level 1) Valedictorian

Posted on

h3c ch ch ch2 ch2 ch3  

 1   2  3   4   5     6 =====> carbon numbering (6 C at main chain)

   ch3 ch3 


IUPAC anme 2,3 dimethylhexane


h3c ch2 ch=ch ch2 ch2 ch3 

   1    2   3   4  5    6   7=====> carbon numbering (7 C at main chain)

Hept-3-ene or 3-heptene [ene-for the double bond and 3 for the location]


ch3 ch3 ch2 ch2 ch2 ch2 ch ch2

8    7    6     5     4       3  2  1 ==> carbon numbering (8 C at main chain)

[numbering will start in such a way that the side chain get attached to the minimum C-location]

the CH3 is attached to 2nd C-atom]


IUPAC name: 2-methyloctane

longcory52's profile pic

longcory52 | Student, College Freshman | (Level 2) eNoter

Posted on

its supposed to be: 

h3c ch ch ch2 ch2 ch3 #1 

     ch3 ch3 

h3c ch2 ch=ch ch2 ch2 ch3 #2


ch3 ch3 ch2 ch2 ch2 ch2 ch ch2 #3 



Name the 3 compounds