Alkanes have the general molecular formula #C_nH_(2n+2)#. Thus, when #n= 1#, the alkane is #CH_4#, when #n = 2#, the alkane is #C_2H_6# etc. If an alkane has a molar mass between 140 and 150, what is the alkene?

1 Answer
Dec 1, 2016

The required alkane is a Decane #(C_10H_22)#.

Explanation:

This is a simple calculation.
The general formula for alkanes is #C_n H_(2n+2)#.

So, an alkane having 10 carbon atoms will surely have 22 hydrogen atoms, according to the given formula.

So, the molar mass of decane is equal to:
#=(10xx12)+(22xx1)# grams.
#=142# grams.

Now, 142 lies between 140 & 150.
So, the alkane is Decane.