McMurry (Kap. 6,3) - Radical reactions.

Question 1

Is a radical reaction reactive or not?

Answer 1

Yes, highly, because it contains an atom with an odd number of electrons in its outer shell (usually 7) compared to an octet stable one.

Question 2

In which ways can a radical achieve a valence shell octet?

Answer 2

1) by abstracting an atom, and one bonding electron from that atom, leaving behind a new radical (radical substitution reaction).

2) A reactant radical might add itself on to a double bond, taking one electron from the double bond anf leaving one behind to form a new radical (radical addition reaction).

see s.149.

Question 3

On page 150, the radical reactions in the LAB requires 3 steps. What are they?

Answer 3

1) initiation: By using UV light, breaking weak bond between two radicals occur - to give a few reactive radicals.

2) propagation: The chain reaction begins, where radical reactions occur either by radical addition reaction or radical addition reaction.

3) termination: Two radicals may crash together and form a stable product, which stops the chain cycle.

Question 4

What is the probability of a radical reaction to terminate?

Answer 4

Low, there is always a small percentage of radicals in a mixture, so the chance that they may collide is small.