10 questions🇬🇧English

💍 Benzene & Aromatic Chemistry – A-level

Chemistry · A-level — benzene's structure, delocalisation evidence, nitration and Friedel–Crafts acylation

Make it your own private quiz and change anything you like

Questions

What is the length of every carbon–carbon bond in a benzene ring?

0.134 nm

0.120 nm

0.139 nm

0.154 nm

20s

Which mixture is used to nitrate benzene?

Concentrated nitric and sulfuric acids

Concentrated nitric acid and AlCl₃

Concentrated sulfuric and hydrochloric acids

Dilute nitric acid on its own

20s

What is the name of the compound C₆H₅NO₂?

Phenylamine

Nitrobenzene

Benzonitrile

Nitrophenol

20s

Cyclohexene has ΔH hydrogenation = −120 kJ mol⁻¹. What value does the Kekulé model predict for benzene?

−120 kJ mol⁻¹

−240 kJ mol⁻¹

−208 kJ mol⁻¹

−360 kJ mol⁻¹

30s

Which electrophile attacks the benzene ring during nitration?

NO₂

NO₂⁺

NO⁺

NO₃⁻

20s

Why is the temperature kept below about 55 °C when making nitrobenzene?

To stop the ring from undergoing addition

To stop the sulfuric acid decomposing

To stop more than one nitro group substituting

To stop the benzene from boiling away

30s

Benzene reacts with ethanoyl chloride in the presence of AlCl₃. What is the organic product?

Chlorobenzene

Ethylbenzene

Phenylethanone

Phenyl ethanoate

30s

Benzene's measured ΔH hydrogenation is −208 kJ mol⁻¹. By how much is it more stable than the Kekulé structure?

120 kJ mol⁻¹

360 kJ mol⁻¹

152 kJ mol⁻¹

208 kJ mol⁻¹

30s

In Friedel–Crafts acylation, how is the AlCl₃ catalyst regenerated?

H₂O reacts with AlCl₄⁻ to form AlCl₃

H⁺ reacts with AlCl₄⁻ to form AlCl₃ and HCl

The acylium ion releases AlCl₃ directly

The ketone product reacts with AlCl₄⁻

30s

Why does benzene usually react with electrophiles by substitution rather than addition?

Its π electron density is higher than in alkenes

The electrophiles are too large to add on

Its C–C bonds are too short to be broken

Substitution keeps the stable delocalised ring

30s