3. Identities of the components in a mixture may be determined by a technique called spiking. Suppose you had run a gas chromatogram on your product and had then deliberately added a drop of a known sample of 3-methylcyclohexene to a drop of your product. What would you expect the new chromatogram to show you?

Explanation:

Suppose we dehydrate 2-methylcyclohexanol, the products formed are 1-methylcyclohexene and 3 methylcyclohexene, where 1-methylcyclohexene tends to be the major product because it has the tendency of more substituted double bond.

In any event, gas chromatography method usually reveals two products with their relative amounts but not their identities.

Now, if we carry out a reaction containing those two products and let's say we have a peak 10:1. Then, we add a little drop of 3-methylcyclohexene to the mixture and carry out the test again.

Let's say that the new ratio is 3:1. Therefore, we can conclude that the minor product is 3-methylcyclohexene. However, if the ratio is larger, let say 20:1, then the original sample's major product is 3-methylcyclohexene.