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Flashcards in C1b Deck (11):
1

How can perfumes be natural or artificial?

-esters are often used in perfumes
-esters are common in natural
-esters can be manufactured synthetically to use as perfumes or flavouring

2

What is the process of esterification?

-carboxylic acid+alcohol-->ester+water
1-mix 10cm3 of both a carboxylic acid and alcohol
2-add 1cm3 of concentrated sulfuric acid as an acid catalyst
3-warm gently for 5 minutes
4-add 150cm3 of sodium carbonate solution to neutralise the acids
5-smell carefully by wafting the smell to your nose
-the fruity-smelling product is the ester

3

What are the needed properties of perfumes?

-easily evaporates or it won't reach any noses
-non-toxic: it mustn't seep through your skin and poison you
-doesn't react with water: or it could react to water in sweat
-doesn't irritate skin: or you can't apply directly to skin
-insoluble in water: if it was soluble in water is would wash off every time you got wet

4

What are peoples opinions on testing cosmetic products on animal?

-worth testing on animals first to check it won't damage humans
-it's wrong to cause suffering to animals just to test the safety of cosmetics (especially when the results may be inconclusive)

5

Why has testing cosmetics on animals been banned in the EU?

-because of concerns of animal welfare

6

What are the properties of a solid?

-strong intermolecular forces of attraction
-particles don't move
-definite shape and volume
-do not flow
-particles vibrate as they get hotter, causing them to expand slightly

7

What are the properties of a liquid?

-some intermolecular forces of attraction
-particles are free to move but tend to stick together
-don't keep a definite shape
-keep the same volume
-will flow to the bottom of a container
-particles constantly moving in random motion
-the hotter the faster they move

8

What are the properties of a gas?

-no intermolecular forces of attraction
-free to move
-travel in straight lines and only interact when they collide
-no define shape or volume
-always fill any container
-particles move constantly with random motion
-hotter=faster

9

How do we smell thing?

-liquid particles are heated they move faster
-some faster than others
-fast-moving particles at the surface will overcome the forces of attraction from the other particles and escape
-this is evaporation
-evaporated particles drift in the air
-smell receptors in our noses pick up the the chemical and we smell it

10

What are the forces like in perfumes?

-the forces of attractions need to be very weak (volatile)
-you only need a little heat energy to evaporate perfume
-its easy for the particles to overcome this attraction and escape

11

What is volatility?

-how easily a liquid evaporates