Topic 4 Introductory organic chemistry and alkanes

Question 1

what is a hydrocarbon

Answer 1

a COMPOUND that only contains hydrogen and carbon

Question 2

How are hydrocarbons classified

Answer 2

saturated and unsaturated

Question 3

What is a saturated hydrocarbon

Answer 3

A compound containing only single bonds. it contains as much hydrogen as possible

Question 4

What is an unsaturated hydrocarbon

Answer 4

A compounds containing one or more double bonds

Question 5

What is a displayed formula

Answer 5

formula showing every atom and every bond

ex: H-C=C-H
I I
H H

Question 6

What is a structural formula

Answer 6

shows unambiguously how every atom is joined together

ex: CH3CH2CH2CH3
CH3-CH2-CH2-CH3

Question 7

What is a skeletal formula

Answer 7

Formula showing the bonds between the carbon atoms. Only atoms other than carbon and hydrogen need to be shown

Question 8

What is a molecular formula

Answer 8

shows the actual number of each atom in a molecule

Question 9

what is an empirical formula

Answer 9

formula showing the number of each atom in the simplest whole-number ratio

Question 10

What is a functional group

Answer 10

A group of atoms in a molecule that is responsible for its chemical reactions and properties

Question 11

What is a homologous series

Answer 11

family of compounds with the same functional group which differ in formula by CH2 from the next member
They have the same functional group, differ by a CH2 unit, have similar chemical properties, same general formula, and show a trend in their physical properties

Question 12

What is Alkanes functional Group

Answer 12

They are not considered to have one

Question 13

What is the general formula of Alkanes

Answer 13

CnH2n+2

Question 14

What is the general formula of Alkenes

Answer 14

CnH2n

Question 15

What is the general formula of Halogenoalkane

Answer 15

CnH2n+1X

Note: X=halogen

Question 16

What is the general formula of Alcohols

Answer 16

CnH2n+1OH

Question 17

What are the products of alkanes burning

Answer 17

water and carbon dioxide

Question 18

What is the relationship between the boiling point and the number of carbon and hydrogen atoms?

Answer 18

The more atoms the higher to boiling point

Question 19

What are structural isomers

Answer 19

compounds with the same molecular formula but a different structural formula

Question 20

What are the two types of structural isomers

Answer 20

chain isomers (based on arrangement of carbon chain) and position isomers (based on position of functional group)

Question 21

what is an addition reaction

Answer 21

when two reactant species combine together to form two product species

Question 22

What is a substitution reaction

Answer 22

When two reactant species combine to form two product species

Question 23

What is an oxidation reaction

Answer 23

when an organic compound is oxidized by an inorganic reagent. The organic compound either gains oxygen or looses hydrogen

Question 24

How is the oxidizing agent displayed?

Answer 24

{O}

note: use your useless imagination and pretend these are square brackets

Question 25

What is a reduction reaction

Answer 25

when an organic compound is reduced by hydrogen and a catalyst or an inorganic reagent. This means the organic compound either gains hydrogen or looses oxygen

Question 26

What is a polymerization reaction

Answer 26

when a very large amount of reactant molecules react together to form one very large product molecule

Question 27

What are the ways in which a covalent bond can break

Answer 27

Heterolytic fission homolytic fission

Question 28

What is homolytic fission

Answer 28

the breaking of a covalent bond where each of the bonding electrons leaves with one species, forming a free radical

Question 29

What is heterolytic fission

Answer 29

the breaking of a con=valent bond so that both bonding electrons are taken by one atom forms a positive and negative ion

Question 30

Definition of free radical????

Answer 30

a species that contains an unpaired electron

Question 31

Definition of electrophile

Answer 31

a species that is attracted to a region of high electron density occurs to the positive ion produced by heterolytic fission and this region id given the symbol S-

Question 32

Definition of electrophile

Answer 32

a species that is attracted to a region of high electron density occurs to the positive ion produced by heterolytic fission and this region id given the symbol S-

Question 33

What is a hazard

Answer 33

something that could cause harm to to a user due to the inherit properties of the substances

Question 34

What is a risk

Answer 34

the chance of a hazard causing harm

Question 35

What is the meaning of a health hazard symbol

Answer 35

warning on skin rashes, eye damage and indigestion

Question 36

what is the meaning of the corrosive symbol

Answer 36

causes skin burns and permanent eye damage

Question 37

what is the meaning of the flammable symbol

Answer 37

can catch fire if heated or comes into contact with a flame

Question 38

what is the meaning of the acute toxicity symbol

Answer 38

can cause life-threatening effects, even in small quantities

Question 39

What apparatus can be used rather than a mercury thermometer

Answer 39

spirit thermometer or digital thermometer

Question 40

What apparatus can be used rather than a tripod, gauze, and Bunsen burner

Answer 40

electrical heating mantle or (more likely) warm water bath

Question 41

What can be used rather than connecting glass tubing with corks and rubber bungs

Answer 41

connecting by ground glass joints as it does not involve the risk of assembling the apparatus

Question 42

What are the main processes needed to convert crude oil into fuel

Answer 42

fractional distillation cracking reforming

Question 43

How does fractional distillation take place

Answer 43

crude oil is heated in a furnace which turns most of it into a vapor, which is then passed into a column near the bottom. There is a temperature gradient in column; it is hotter near the bottom and cooler near the top. Different fractions condense at different heights in the column, depending on the boiling temperature range of the molecules in the fraction.

Question 44

What is the difference between the molecules at the top of the column and the bottom

Answer 44

larger molecules, longer chains and higher b.p

Question 45

What is the process of cracking

Answer 45

long chained alkanes are passed through a heated catalyst, which is usually zeolite (aluminium+silicon+oxygen) this causes large molecules to break up into smaller ones

Question 46

What is reforming

Answer 46

the conversion of straight-chained hydrocarbons into branched chain and cyclic hydrocarbons along with hydrogen as a useful by-product

Question 47

What pollutants are emitted during the combustion of alkane fuels

Answer 47

carbon monoxide, oxides or sulfur, nitrogen, carbon particulates, and unburned hydrocarbons

Question 48

Dangers of carbon monoxide

Answer 48

toxic gas that acts by prevents the transport of oxygen around the body. It is colorless and odorless

Question 49

Dangers of oxides of sulfur and oxides of nitrogen

Answer 49

contribute to the formation of acid rain which causes a lot of environmental damage to crops and forests as well as aquatic life in lakes and rivers

Question 50

What can be used to reduce the amounts of pollutants

Answer 50

catalytic converters

Question 51

How do catalytic converters work?????

Answer 51

uses a three way catalyst of platinum, rhodium and palladium which are spread thinly over a honeycomb mean to increases the surface area for reaction the catalytic converter will oxidize carbon monoxide and unburnt hydrocarbons. Carbon monoxide and Nitrogen monoxide will also react together.