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Flashcards in C1b Deck (11)
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1
Q

How can perfumes be natural or artificial?

A
  • esters are often used in perfumes
  • esters are common in natural
  • esters can be manufactured synthetically to use as perfumes or flavouring
2
Q

What is the process of esterification?

A

-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
Q

What are the needed properties of perfumes?

A
  • 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
Q

What are peoples opinions on testing cosmetic products on animal?

A
  • 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
Q

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

A

-because of concerns of animal welfare

6
Q

What are the properties of a solid?

A
  • 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
Q

What are the properties of a liquid?

A
  • 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
Q

What are the properties of a gas?

A
  • 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
Q

How do we smell thing?

A
  • 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
Q

What are the forces like in perfumes?

A
  • 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
Q

What is volatility?

A

-how easily a liquid evaporates