Naming unbranched hydrocarbons.

https://www.youtube.com/watch?v=OSB_1x08UHc

What is saturated / unsaturated hydrocarbon

Hydrocarbon withno double covalent bond and only single bonds is saturated

Hydrocarbons with double / triple covalent bond between carbon atoms is unsaturated

How do we name butene

The double bond can be in two different posititons.

To name them , we show position of double bond, we can do this by numbering carbon atoms.

In first molecule, double bond lies between carbon 1 and 2, so we call it but-1-ene (since 1 is the lowest out of 1 and 2)

On the bottom, the double bond lies between carbon 2 and 3 so we called it but-2-ene

What end do you start numbering carbon atoms from

The rule is that you choose the end that produces the lowest possible numbers, so but-1-ene is correct name

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