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Question 1

what is the word equation to create an ester

Answer 1

alcohol + acid = ester + water

Question 2

describe a simple experiment to make an ester

Answer 2

warm an acid (e.g butanoic acid) with an alcohol (eg pentanol) in a beaker and add a few drops of concentrated sulfuric acid (catalyst)
add aqueous sodium carbonate to neutralise any remaining acid
waft towards nose from a distance to test smell

Question 3

list the properties a perfume needs and why

Answer 3

• evaporates easily (volatile) so the perfume particles easily reach the nose
• non-toxic so the wearer is not poisoned
• non-reactive with water so does not react with sweat
• non-irritant to skin otherwise it could not be applied to skin
• insoluble in water so is not washed off easily

Question 4

why are perfumes volatile (kinetic theory)

Answer 4

• particles need sufficient energy to evaporate, in order to overcome the attraction to other molecules of the liquid
• weak attractions between the perfume particles so they are easily overcome

Question 5

give the other main use of esters (not perfumes)

Answer 5

solvents

Question 6

what is a solute and a solvent, and what do they both make

Answer 6

solvent is something that dissolves other things, solute is the solid that dissolves, they create a solution (mixture of the two that does not seperate out)

Question 7

why does water not remove nail varnish

Answer 7

• attraction between water molecules is stronger than attraction between water molecules and nail varnish molecules
• attraction between nail varnish molecules is stronger than attraction between nail varnish and water molecules

Question 8

why has testing on animals been banned in the EU

Answer 8

• immoral to test on animals/cruel
• animals may not react the same way as humans
• ways of testing with human skin e.g growing skin cells or using human test subjects

Question 9

why might someone support animal testing

Answer 9

• saves human lives/prevents suffering

- animals have less rights than us