Coding for the type of compound

1 mark · Easy

State the general rule for numbering the carbon atoms in a chain when naming an alkene.

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Number from the end which gives the double bond the smallest possible number.

Also accept: Number the chain so the double bond gets the lowest possible number

Common mistakes: Saying number from left to right or from the end with more H

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Marking points

B1 · 1 mark · States that numbering starts from the end closest to the double bond to give it the lowest possible number.

Worked solution

Number the carbon chain so that the double bond has the smallest possible number.