What is the molecular formula for an 18 carbon alkane

 C18 H38

Explanation: Alkane follows the general formula of CnH2n+2.

Here n = 18 , substituting the value of n in the above formula, we get

C 18 H 2(18)+2 =   C18 H38

The name of this alkane is Octadecane and it can also be written like this -

Ch3 (ch2)16 Ch3

Octadecane is the straight chain alkane having 18 carbon atoms .

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