Nature's Chemistry

Question 1

alcohol

Answer 1

carbon compounds which contain the hydroxyl functional group, -OH

Question 2

alkaline hydrolysis

Answer 2

process which produces soaps from edible fats and oils. hydrolysis produces three fatty acid molecules and one glycerol molecule. the fatty acid molecules are neutralised by the alkali, forming water-soluble ionic salts called soaps.

Question 3

amide links

Answer 3

a group of atoms formed by condensation polymerisation of amino acids during the formation of proteins. Can be identified as -CONH- and occurs where each pair of amino acids has joined together.

Question 4

amino acid

Answer 4

compounds of general formula H2NCHRCOOH which link by condensation reactions to form proteins

Question 5

carboxylic acid

Answer 5

carbon compounds which contain the carboxyl functional group, -COOH

Question 6

condensation

Answer 6

reaction in which two molecules combine to form a larger molecule at the same time eliminating a small molecule (such as water)

Question 7

denaturing

Answer 7

physical alteraction of the molecular shape of a protein, or other molecule, as a result of temperature or pH changes

Question 8

detergent

Answer 8

substances with non-polar hydrophobic tails and ionic hydrophilic heads which remove oil and grease in the same way as soaps but do not form soap scum with hard water

Question 9

emulsion

Answer 9

a mixture of liquids where small droplets of one liquid are dispersed in another liquid.

Question 10

emulsifier

Answer 10

a substance which prevents non-polar and polar liquids separating into layers. can be made by reacting edible oils with glycerol

Question 11

enzymes

Answer 11

protein molecules which act as catalysts in biological processes

Question 12

essential amino acids

Answer 12

amino acids that cannot be made by the body and must be obtained from the diet

Question 13

esters

Answer 13

carbon compounds formed when alcohols react with carboxylic acids by condensation

Question 14

fats

Answer 14

esters formed from one molecule of glycerol and three molecules of (usually saturated) long-chain carboxylic acids. have melting points high enough to be solid at room temperature.

Question 15

hydrogenation

Answer 15

the addition of hydrogen to a carbon to carbon multiple bond

Question 16

hydrolysis

Answer 16

the breakdown of a molecule by reaction with water

Question 17

isomers

Answer 17

compounds which have the same molecular formula but different structural formulae

Question 18

oils

Answer 18

esters formed from one molecule of glycerol and three molecules of (usually unsaturated) carboxylic acids. have melting points low enough to be liquid at normal room temperature.

Question 19

peptide links

Answer 19

an amide link which is found in a living organism (in proteins)

Question 20

proteins

Answer 20

biological polymers of small molecules called amino acids

Question 21

saturated

Answer 21

a compound in which all carbon-carbon covalent bonds are single bonds

Question 22

soaps

Answer 22

salts of fatty acids; have an ionic head that is water soluble and a covalent tail that is soluble in oil.

Question 23

triglycerides

Answer 23

molecules formed through the condensation of one glycerol molecule with three fatty acids molecules

Question 24

unsaturated

Answer 24

molecule with at least one carbon to carbon double bond

Question 25

volatility

Answer 25

a measure of how easily a molecule will evaporate

Question 26

aldehyde

Answer 26

an organic compound with a carbonyl functional group (C=O) at the end of the molecule

Question 27

antioxidant

Answer 27

compounds that prevent oxidation reactions in other compounds by being oxidised themselves. examples include vitamin E and C

Question 28

essential oils

Answer 28

concentrated extracts of volatile, non-water soluble aroma compounds from plants

Question 29

free radicals

Answer 29

atoms or molecules containing unpaired electrons

Question 30

free radical scavengers

Answer 30

molecules which can react with free radicals to form stable molecules and prevent chain reactions

Question 31

isoprene

Answer 31

the units which join together to make terpenes. systematically named 2-methylbuta-1,3-diene

Question 32

ketone

Answer 32

an organic compound with a carbonyl functional group (C=O) within the carbon chain (i.e. not on one of the end carbons)

Question 33

oxidation (of carbon compounds)

Answer 33

a reaction which results in the increase in the oxygen to hydrogen ratio

Question 34

reduction (of carbon compounds)

Answer 34

a reaction which results in a decrease in the oxygen to hydrogen ratio

Question 35

terpenes

Answer 35

one of the primary constituents of essential oils; unsaturated hydrocarbons formed by joining together isoprene units