Hydrocarbons: common misconceptions

If your child says… “Turning it makes another isomer.”

Ask together

Which carbon has different neighbours in the two butane drawings?

What’s true

Structural isomers need different connections, while keeping the same formula.

If your child says… “Adding hydrogen rearranges the carbon chain.”

Ask together

Which carbon has gained a different carbon neighbour?

What’s true

Ordinary hydrogenation preserves the carbon framework.

If your child says… “Every repeating step needs more ultraviolet light.”

Ask together

Where did the new chlorine radical come from?

What’s true

The repeating steps regenerate radicals, which have an unpaired electron.

If your child says… “A double bond turns freely too.”

Ask together

Can the sideways overlap survive when one end turns?

What’s true

Twisting a double bond disrupts its sideways pi overlap.

If your child says… “Bromine goes on the end carbon without peroxide.”

Ask together

Which carbon carries the positive charge in the line you wrote?

What’s true

Without peroxide, propene mainly forms 2-bromopropane through the more stable carbocation.

If your child says… “One hydrogen pair turns ethyne into ethane.”

Ask together

After the first addition, which bond still accepts hydrogen?

What’s true

Complete hydrogenation adds two hydrogen molecules across each triple bond.

If your child says… “Substitution permanently destroys the ring’s aromatic stability.”

Ask together

Where do the carbon–hydrogen bond’s electrons go when the proton leaves?

What’s true

The final substitution product regains continuous electron sharing around the ring.

If your child says… “A nitro group makes the ring react faster.”

Ask together

Does withdrawing electrons make this ring more attractive to an electron-seeking attacker?

What’s true

Nitro withdraws electron density, making the ring less reactive toward electrophiles.