Smells Flashcards
(17 cards)
What 5 features makes a good perfume and why?
>Evaporates: reaches nose >Non-toxic: does not poison >No reaction with water: doesn't react with perspiration >Non-irritant: can be sprayed on skin >Insoluble in water: not washed off skin
What is the word equation to make an ester?
alcohol + acid > ester + water
-To make a perfume the chemical ester is needed
What does volatile mean?
-When a substance evaporates easily
Why is it important that perfumes are volatile?
- Fast moving particles at room temperature
- Weak attraction between particles in the liquid
- Forces of attraction easily broken between molecules in the liquid
- Particles with lots of energy can escape attraction to other molecules
- Escape from surface of liquid as gas
What does soluble mean?
A substance that dissolves in a liquid
What is the name for a substance that dissolves in a solution?
A solute
What is the liquid called that a solute dissolves into?
A solvent
What solvent can be used to remove nail varnish?
propanone
What solvent removes wine?
salt water
What solvent removes blood?
water
What solvent removes oil?
methylated spirit
What is a solution?
A solute and solvent that does not separate
What solvent can clean grease?
oil
Why is animal testing banned in UK and EU?
>animals have no control/choice >harms animals >public opinion is strongly against it >causes animals unnecessary suffering >there are other methods of testing that do less damage to living things
Describe how gas molecules move?
They have a high kinetic energy and move rapidly and randomly
How does evaporation occur?
> Liquids have less kinetic energy
Weakly attracted to each other
When some particles increase their KE, the force of attraction is overcome and particles escape from the liquid surface in the form of gas
Why does water not dissolve nail varnish?
The force of attraction between two water molecules is stronger than between a water molecule and a nail varnish molecule, and vice versa.