organic

Question 1

do alkanes or alkenes have a double bond

Answer 1

alkenes

Question 2

general formula of alkenes

Answer 2

CnH2n

Question 3

which type of hydro carbon is unsaturated and why

Answer 3

alkenes because of the double bond. This bond also makes them more reactive

Question 4

are alkanes saturated or unsaturated

Answer 4

saturated

Question 5

how to remember if rules about hydro carbons

Answer 5

alkenes are unsaturated because of their double bond - They have bonds that could be use in other places so they are “unsaturated”

Question 6

what is the empirical formula

Answer 6

simplest whole number ratio of atoms of each element in a compound

Question 7

what is a homologous series

Answer 7

group of compounds that can all be represented by the same general formula

Question 8

what is the functional group for alkenes

Answer 8

C=C

Question 9

what is the functional groups for alcohols

Answer 9

O-H

Question 10

what is the functional group for carboxylic acids

Answer 10

C=OOH

Question 11

what is the functional group for esters

Answer 11

c=oo

Question 12

what is an isomer

Answer 12

same molecular formula but atoms are arranged differently or same number of protons different number of neutrons

Question 13

how is crude oil split up

Answer 13

The oil is heated until it is a gas. They then enter a fractionating column, which is hotter at the bottom and cooler at the top. When they reach the part of the column that is lower than their boiling point they condense and drain out of the column. Shorter chain hydro carbons have lower boiling points. Bubble caps stop the liquids from running back down the column

Question 14

properties of long chain hydrocarbons

Answer 14

high poling points and viscous (thick and gloopy)

Question 15

why are long chain hydro carbons split

Answer 15

short chain hydro carbons are in higher demand so they are split into shorter chain hydro carbons

Question 16

what type of reaction is cracking

Answer 16

thermal decomposition - breaking down molecules into smaller ones by heating

Question 17

what does cracking produce

Answer 17

alkenes

Question 18

what are the conditions for cracking

Answer 18

vaporized hydro carbons are passes over a powdered catalyst at about 600-700 degrees. Silica or alumina are used as a catalyst.

Question 19

complete combustion equation

Answer 19

hydrocarbon+oxygen->carbon dioxide + water

Question 20

what is incomplete combustion

Answer 20

It happens when there is not enough oxygen, as well as carbon dioxide and water it produces carbon monoxide - toxic gas and carbon in form of soot

Question 21

why is carbon monoxide dangerous

Answer 21

it binds with haemoglobin to stop red blood cells carrying oxygen around the body = fainting, coma or death

Question 22

what is acid rain caused by

Answer 22

sulfur dioxide and nitrogen oxides

Question 23

what does sulfur dioxide come from

Answer 23

sulfur impurities in hydrocarbon fuels

Question 24

how are nitrogen oxides made

Answer 24

when the temperature is high enough for nitrogen and oxygen in the air to react e.g. in car engines

Question 25

what happens when sulfur dioxide and nitrogen oxides mix with water vapour in clouds

Answer 25

they form dilute sulfuric acid and nitric acid = acid rain

Question 26

what happens when halogens and alkanes react

Answer 26

they form haloalkanes. A hydrogen atom is substituted with a halogen = substitution reaction.

Question 27

what happens when halogens react with alkenes

Answer 27

they form haloalkanes. This is an addition reaction because the c-c double bond is split open and the halogens are added on.

Question 28

how do you test for alkene

Answer 28

shake with orange bromine water and it will go colourless

Question 29

what is the general formula for alcohols

Answer 29

CnH2n+1OH

Question 30

what the is alcohols functional group

Answer 30

OH

Question 31

what happens when alcohols are oxidized

Answer 31

they form carboxylic acids

Question 32

what is an oxidizing agent used to turn alcohol to carboxylic acids

Answer 32

potassium dichromate (VI) in dilute sulfuric acid

Question 33

when is microbial oxidization

Answer 33

when some organisms use alcohols as an energy source, they use oxygen in the air to oxidize alcohols.

Question 34

what happens when alcohols are burnt

Answer 34

they are oxidised

Question 35

how is ethanol produced by ethene and steam

Answer 35

Ethene reacts with steam to make ethanol. This is an addition reaction because water is added to the molecule. The reaction needs a temp of 300 degrees and 60-70 atmospheres. Phosphoric acid is used as a catalyst.

Question 36

pros of cons of ethene + steam

Answer 36

cheap , crude oil is non- renewable

Question 37

how is ethanol made by fermentation

Answer 37

sugar is converted into ethanol using yeast. Yeast cells contain an enzyme. The mixture need to be at 30 degrees and have anaerobic conditions as other wise the ethanol would turn into ethanoic acid.

Question 38

pros and cons of fermentation

Answer 38

renewable resources, ethanol isn't very concentrated and needs to be distilled and purified.

Question 39

what is the carboxylic acid functional group

Answer 39

COOH

Question 40

what do carboxylic acids produce when reacting with metal carbonates

Answer 40

salt, water , carbon dioxide

Question 41

what do carboxylic acids produce when reacting with metals

Answer 41

salt and hydrogen

Question 42

how is vinegar made

Answer 42

ethanoic acid is dissolved in water to make vinegar

Question 43

what is the ester functional group

Answer 43

COO

Question 44

how are esters formed

Answer 44

alcohol and a carboxylic acid an acid catalyst is used e.g. concentrated sulfuric acid

Question 45

how do you make esters in the lab

Answer 45

add a few drops of concentrated sulfuric acid to a boiling tube using a dropping pipette, add 10 drops of ethanoic acid, add an equal volume of ethanol. Place the beaker in a beaker of water and place on a tri pod. Use a Bunsen burner till the water starts to boil, then turn it off. After 1 minute remove the tube and allow it it cool. Then pour the mixture into a test tube of sodium carbonate solution and mix. A layer of the ester should form on top of the solution.

Question 46

why are esters useful

Answer 46

used in perfumes and food flavourings

Question 47

what are addition polymers made from

Answer 47

un saturated monomers

Question 48

how do you draw the repeat unit of a polymer

Answer 48

Question 49

why are polymers hard to dispose of

Answer 49

addition polymers are inert - the c-c bonds are strong, they take ages to bio degrade and burning produces toxic gases

Question 50

what are polyesters

Answer 50

condenstation polymers

Question 51

what are biodegradable polyesters known as and why

Answer 51

biopolyesters- they are broken down by bacteria and other living organisms in the environment