organic chemistry - organic compounds

Question 1

what are alkenes

Answer 1

a homologous series of hydrocarbons. they are more reactive than alkanes. they have a double covalent bond between 2 carbon atoms in their chain. known as unsaturated hydrocarbons as they contain 2 fewer hydrogen than alkanes.

Question 2

why are alkenes more reactive than alkanes

Answer 2

the c=c double bond can open up to become a single bond allowing the 2 carbon atoms to react with other atoms

Question 3

what are the first 4 alkene atoms

Answer 3

ethane, propane, butane, pentane

Question 4

what is the general formula for an alkene

Answer 4

CnH2n

Question 5

what can you do to find the difference between an alkene and an alkane

Answer 5

add orange bromine water to them. Alkene will react and decolorize orange bromine

Question 6

what is the equation for incomplete combustion of an alkene

Answer 6

alkene + oxygen = carbon + carbon monoxide + co2 + water

Question 7

how do you tell visually that incomplete combustion has happened

Answer 7

Smokey yellow flame and less energy

Question 8

what is a functional group

Answer 8

a group of atoms e.g. c=c that determine how a compound typically reacts.

Question 9

what is the hydrogeneration of alkenes

Answer 9

hydrogen reacts with double bonded carbon and form the equivalent saturated alkane. e.g butene becomes butane . happens in the presents of a catalyst

Question 10

explain forming alcohol from alkenes

Answer 10

ethene reacts with steam in the presents of a catalyst. The reaction mixture is passed into a condenser.
ethanol and water have a higher boiling point than ethene so they condense while ethene gas is recycled back into the condenser. the alcohol is then purified through fractional distillation .

Question 11

what can lead to more than one form of alcohol being produced

Answer 11

the -OH group can add to either of the carbons from the C=C bond.

Question 12

how does the position of the c=c bond effect the alcohol produced

Answer 12

if the bond is in a different place, it can affect the type produced

Question 13

addition of halogens to alkenes

Answer 13

react together in addition reactions
the molecules formed are saturated
with the C=C carbons becoming bonded to a halogen atom

Question 14

bromine and ethane react to form what

Answer 14

dibromoethane

Question 15

butane and bromine react to form what

Answer 15

dibromobutane

Question 16

what is addition polymerisation

Answer 16

when lots of small akene molecules open up their double bonds to join to form long chain molecules called polymers

Question 17

what is a trait of the repeating pattern of polymers

Answer 17

4 groups arranged around a main chain containing 2 carbon atoms

Question 18

how do you tell what a polymer is going to be called

Answer 18

name of alkene with poly infront

Question 19

how do you draw the displayed formula of a polymer

Answer 19

replace the double bond of the alkene with a single bond with the bonds coming off each ends with brackets and an n.

Question 20

what are alcohols

Answer 20

group of compounds that make up a homologous series all containing -OH functional group.

Question 21

what is the general formula for an alcohol

Answer 21

CnH2n+1OH

Question 22

what is the naming system of alcohols

Answer 22

replace the final e of alkane with an ol

Question 23

what are the chemical formulas for the first 4 alcohols

Answer 23

methanol CH3OH
ethanol C2H5OH
propanol C3H7OH
butanol C4H9OH

Question 24

how do u tell if something is an alcohol

Answer 24

name ends in ol

has OH in it

Question 25

alcohols burn in the air to produce what

Answer 25

carbon dioxide and water

Question 26

3 similarities between the first 4 alcohols are what

Answer 26

dissolve completely in water to form neutral solutions they react with sodium and produce hydrogen as a product they can be oxidised by reacting with oxygen

Question 27

what is formed when an alcohol is oxidised

Answer 27

carboxylic acid

Question 28

what in the name of a chemical compound shows something is a carboxylic acid

Answer 28

ends in oic

Question 29

what is the main type of alcohol in drinks

Answer 29

ethanol

Question 30

why is ethanol used in perfumes and aftershave lotions

Answer 30

it can mix with oils and water

Question 31

what is methylated spirit

Answer 31

ethanol with chemicals added. used to clean paint brushes and fuel. poisonous to drink so purply blue dye is added

Question 32

why is ethanol used in fuel spirit burners

Answer 32

burns fairly cleanly and non smelly. can also be mixed with petrol and used in cars so the more you add the less pollution is produced

Question 33

what is the word equation for the fermentation of sugar

Answer 33

sugar = carbon dioxide + ethanol | yeast

Question 34

what conditions are needed for fermentation

Answer 34

in solution 37 degrees slightly acidic anaerobic conditions

Question 35

what functional group do carboxylic acids have in common

Answer 35

COOH with the carbon atom having a double bond with an oxygen aton and a single bond with OH

Question 36

what is the displayed formula for ethanoic acid

Answer 36

CH3COOH when drawing carboxylic acids always do COOH at theend

Question 37

carboxylic acids react with carbonates to form co2 water and a salt. what do the salts formed end in

Answer 37

anoate

Question 38

what is a property of carboxylic acids to do with water

Answer 38

they dissolve in water, when they do this they ionise and release H+ ions which make the solution acidic

Question 39

why are carboxylic acids weak acids

Answer 39

only partially ionise in water

Question 40

what is the functional group of esters

Answer 40

COO

Question 41

how are esters formed

Answer 41

alcohol + carboxylic acid arrow ester + water | in presents of acidic catalyst

Question 42

what is condensation polymerisation

Answer 42

monomers that contain 2 functional groups. when they react bonds form between them making polymer chains. for each new bond a small molecule is lost like water

Question 43

how are ester links formed

Answer 43

when dicarboxylic acid reacts with diols in a condensation reaction

Question 44

what may make a chain longer in a polyester

Answer 44

if the functional group at the end of the ester link react in condensation reaction. when this also happens its known as condensation polymerisation and it makes a polyester

Question 45

how may monomers types are there in addition polymerisation

Answer 45

only one which is a alkene containing a c=c bond

Question 46

in condensation polymerisation you can have one monomer type as long as it has 2 different functional groups

Answer 46

you need 2 reactive functional groups on each mometer for condensation polymerisation

Question 47

what is the difference between the number of products in addition polymerisation and condensation polymerisation

Answer 47

in addition one type of product is being formed ( the polymer) in condensation a small molecules is also formed

Question 48

what does an amino acid consist of

Answer 48

2 different functional groups - a basic amino group (NH2) and an acidic carboxyl group ( COOH )

Question 49

what kind of polymers do amino acids produce

Answer 49

polypeptides

Question 50

what is the process called by which amino acids produce polypeptides

Answer 50

condensation polymerisation

Question 51

what are proteins

Answer 51

one or more long chains of polypeptides

Question 52

what are 4 uses of proteins in the human body

Answer 52

enzymes work as cataiyst for reactions haemoglobin antibodies majority of body tissue

Question 53

what gives proteins different properties and shapes

Answer 53

the order of amino acids

Question 54

what is the structure of DNA called

Answer 54

double helix structure

Question 55

DNA is made up of 2 polymer chains called what

Answer 55

nucleotides which each contain a small molecule called a base

Question 56

what are the initials of the 4 bases of nucleotides

Answer 56

A C G T

Question 57

what keeps the 2 strands of nucleotides together in DNA

Answer 57

the bases pair up to form cross links

Question 58

what do the order of the bases in DNA do

Answer 58

act as a code for an organisms genes

Question 59

what does sugar contain

Answer 59

carbon oxygen hydrogen

Question 60

sugars react through polymerisation reactions to form polymers such as starch and cellulose

Answer 60

starch is used as an form of chemical energy in plants