Ch3c (ch2ch3) 2 (ch2) 5ch3 naming

H3C - - C - - CH2 - - CH2 - - CH2 - - CH2 - - CH2--CH3

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CH2 - - CH3

Observe the longest chain. Then start counting from the branching side.

1 2 3 4 5 6 7 8

H3C - - C - - CH2 - - CH2 - - CH2 - - CH2 - - CH2--CH3

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CH2 - - CH3

So there are 8 carbons in the long chain means Octane.

Now, there is a ethyl group at 2nd carbon.

So, it is 2-ethylocatane

2-ethylocatane