[rtkt01]

 Here's the question.

 Draw condensed structures for

 2-methyl-3-ethylpentane.

 2,2,4-trimethylpentane.

 2,2,3,3-tetramethylpentane

 3,4,4,5-tetramethylheptane

  Here's what I got. 

 CH3CH2CH(CH2CH3)CH(CH3)2

 (CH3)2CHCH2C(CH3)3

 CH3CH2C(CH3)2C(CH3)3

 CH3CH2CH(CH3)C(CH3)2CH(CH3)CH2CH3

  There's another question.

 Draw structural formula for a tertiary amine containing only secondary carbons

     Y
     N
    /  \
   /\  /\

 Is there anything wrong with my answers?

 I'm still not completly sure about condensed structures.

                                           CH3
                                            l
 Is it that I can write either CH3CCH2CH2CH2CH2CH3 or CH3C(CH3)2CH2CH2CH2CH2CH3 if question asks to draw c
                                            l
                                           CH3
ondensed structures for 2,2-dimethylheptane ?


 

[Fridushka]

                                           CH3
                                            l
 Is it that I can write either CH3CCH2CH2CH2CH2CH3 or CH3C(CH3)2CH2CH2CH2CH2CH3 if question asks to draw c
                                            l
                                           CH3
ondensed structures for 2,2-dimethylheptane ?

Well here in order to make more condensed structure you have to do the following:
Write this: CH3C(CH3)2CH2CH2CH2CH2CH3 ~~ CH3C(CH3)2(CH2)4CH3
Well here you have to count how many CH2 are there next to each other and write the way i wrote it..

[rtkt01]

Well here in order to make more condensed structure you have to do the following:
Write this: CH3C(CH3)2CH2CH2CH2CH2CH3 ~~ CH3C(CH3)2(CH2)4CH3
Well here you have to count how many CH2 are there next to each other and write the way i wrote it..


Thank you for a reply.

How about my answers to 5 questions ?  Did I get those correctly?

[Fridushka]

Well the 1st 4 question are right  ..but what about the 5th?! well i didn't get well the drawing, but are all the carbons 2^o? as it seems N is 3^o thats fine...although i'm not 100% sure for the 5th one

[rtkt01]

Well the 1st 4 question are right  ..but what about the 5th?! well i didn't get well the drawing, but are all the carbons 2^o? as it seems N is 3^o thats fine...although i'm not 100% sure for the 5th one

I think that an answer for the 5th question is tricyclopropylamine.  Is that right?

[AWK]

Both - triisopropyl- and tricyclopropyl- amines are good examples cocerning carbon atoms joined to nitrogen, but in fact tricyclopropylamine contains only secondary carbon atoms

[Fridushka]

I think that an answer for the 5^th question is tricyclopropylamine.  Is that right?

Now its right ..but what you drew was more like triisopropyl in which not all the carbons were 2^o..

[rtkt01]

 Thank you so much for replies.

[Fridushka]

You're welcome

[rtkt01]

 How does this look ?

Question: Draw condensed structures for 10 of 75 consitituional isomers of C10H22, and give the IUPAC name for each structure you drew.

My answer:

CH3(CH2)8CH3 Decane

CH3(CH2)6CH(CH3)2 2-methylnonane

CH3(CH2)5CH(CH3)CH2CH3 3-methylnonane

CH3(CH2)4CH(CH3)CH2CH2CH3 4-methylnonane

(CH3CH2CH2CH2)2CHCH3 5-methlnonane

CH3(CH2)5C(CH3)3 2,2-dimethyloctane

CH3(CH2)4C(CH3)2CH2CH3 3,3-dimethyloctane

CH3(CH2)3C(CH3)2CH2CH2CH3 4,4-dimethyloctane

CH3(CH2)4CH(C2H5)CH2CH3 3-ethyloctane

CH3(CH2)3CH(C2H5)CH2CH2CH3 4-ethyloctane

[Fridushka]

Well they are right but some places you can make it more condensed by writing CH2CH2 as (CH2)2..
and by the way it 5methylnonane..although I know that you have just forgotten to write that "y"