15. skin care Flashcards Preview

Higher Chemistry 2020-2021 > 15. skin care > Flashcards

Flashcards in 15. skin care Deck (14)
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1
Q

What is a free radical?

A

A species ( atom or group of atoms) with an unpaired electron

2
Q

What causes free radical formation in the atmosphere?

A

UV light

3
Q

What is meant by “homolytic fission” of a covalent bond?

A

When both atome leave with one electron each from the bond.

4
Q

What type of covalent bonds are likely to break by homolytic fission?

A

Non-polar bonds where each atom has a similar electronegativity

5
Q

What can cause free radical formation oin the body?

A
6
Q
A
7
Q

What are the 3 steps in a free radical chain reaction?

A
  1. Initiation
  2. Propagation
  3. Termination
8
Q

Which step is shown below?

A

Initiation

9
Q

Which step is shown below?

A

propagation (step 1)

10
Q

What step is shown below?

A

propagation (step 2)

11
Q

What steps are shown below?

A

Termination

12
Q

what are the 2 ways that sun creams work?

A
13
Q

How do free radicals scavengers work?

A
  • Donating electrons to free radical
  • form covalent bonds with free radical
14
Q

What do some skin creams contain to help combat free radical damage?

A

Free radical savengers