L6C Organic Quiz

What is an aromatic hydrocarbon (also known as an arene)?

• Have branched or unbranched chains of carbon atoms or rings of carbon atoms
• Contain rings of carbon atoms in which there are delocalised electrons
• Have only single bonds between atoms
• Contain only double bonds in between carbon atoms

What does an addition reaction of but-2-ene and chlorine produce?

• an alkene and water

• alkane and hydrogen

• halogenoalkane

• halogenoalkene

Which of the following is NOT a stage of the free-radical substituition?

• Initiation
• Substitution
• Termination
• Propagation

What is homolytic fission?

• Bond breaks unevenly with one of the bonded atoms receiving both electrons from the bonded pair.
• Sunlight provides energy to break the bond.
• The bond breaks evenly and each bonding atom receives one electron from the bonded pair.
• The bond breaks evenly and each bonding atom receives two electrons from the bonded pair.

Why do we need UV light for free radical substitution?

• The energies in UV light are perfect for breaking the bond between Chlorine, for example
• It's a pretty colour
• UV controls the reaction
• We don't need it

What is an electrophile?

• both electrons from a covalently bonded pair are accepted by one atom

• a molecule or substance that has a tendency to donate electrons

• an atom that attracts a pair of electrons to itself

• an atom or molecule that accepts an electron pair to make a covalent bond

What kind of light is required in order to form a chlorine free radical?

• UV

• IR

• Green

• No light

What colour do alkenes turn bromine water?

• Colorless
• Yellow
• Orange
• Purple

What happens when you add a alkene to potassium manganate (VII) under acidic conditions?

• decolourises from purple

• decolourises from brown/orange

• two layers form

• no change

What is an electrophile?

• They are positive ions or molecules with a vacant outer orbital that attacks negative ions ore negative centres in molecules
• They are negative ions or molecules with a full outer orbital which attack positive ions or positive centres in a molecule
• They are positive ions or molecules with a full outer orbital that attack negative ions or negative centres in molecules
• They are positive ions or molecules with a vacant outer orbital that attacks positive ions or positive centres in molecules