2.9. Skincare

Question 1

What is UV ( ultraviolet) radiation?

( LO 114 )

Answer 1

A high-energy form of electromagnetic radiation that is present in sunlight

Question 2

What are negative effects of UV radiation?

( LO 114 )

Answer 2

Question 3

What is a free radical?

(LO 115)

Answer 3

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

Question 4

What causes free radical formation in the atmosphere?

( LO 115/6)

Answer 4

UV light

Question 5

What are the 2 ways that sun creams work?

( LO 114 / 119)

Answer 5

Question 6

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

Answer 6

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

Question 7

What can cause free radical formation in the body?

Answer 7

Question 8

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

( LO 116/7/8)

Answer 8

1. Initiation
2. Propagation
3. Termination

Question 9

Which step is shown below?

( LO 116)

Answer 9

Initiation

Question 10

Which step is shown below?

( LO 117 )

Answer 10

propagation (step 1)

Question 11

What step is shown below?

( LO 117 )

Answer 11

propagation (step 2)

Question 12

What steps are shown below?

Answer 12

Termination

Question 13

How do free radicals scavengers work?

Answer 13

• Donating electrons to free radical
• • form covalent bonds with free radical
• • prevent free radical reactions from occuring

Question 14

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

( LO 119 )

Answer 14

Free radical savengers