Topic 4 Introductory organic chemistry and alkanes Flashcards
what is a hydrocarbon
a COMPOUND that only contains hydrogen and carbon
How are hydrocarbons classified
saturated and unsaturated
What is a saturated hydrocarbon
A compound containing only single bonds. it contains as much hydrogen as possible
What is an unsaturated hydrocarbon
A compounds containing one or more double bonds
What is a displayed formula
formula showing every atom and every bond
ex: H-C=C-H
I I
H H
What is a structural formula
shows unambiguously how every atom is joined together
ex: CH3CH2CH2CH3
CH3-CH2-CH2-CH3
What is a skeletal formula
Formula showing the bonds between the carbon atoms. Only atoms other than carbon and hydrogen need to be shown
What is a molecular formula
shows the actual number of each atom in a molecule
what is an empirical formula
formula showing the number of each atom in the simplest whole-number ratio
What is a functional group
A group of atoms in a molecule that is responsible for its chemical reactions and properties
What is a homologous series
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
What is Alkanes functional Group
They are not considered to have one
What is the general formula of Alkanes
CnH2n+2
What is the general formula of Alkenes
CnH2n
What is the general formula of Halogenoalkane
CnH2n+1X
Note: X=halogen
What is the general formula of Alcohols
CnH2n+1OH
What are the products of alkanes burning
water and carbon dioxide
What is the relationship between the boiling point and the number of carbon and hydrogen atoms?
The more atoms the higher to boiling point
What are structural isomers
compounds with the same molecular formula but a different structural formula
What are the two types of structural isomers
chain isomers (based on arrangement of carbon chain) and position isomers (based on position of functional group)
what is an addition reaction
when two reactant species combine together to form two product species
What is a substitution reaction
When two reactant species combine to form two product species
What is an oxidation reaction
when an organic compound is oxidized by an inorganic reagent. The organic compound either gains oxygen or looses hydrogen
How is the oxidizing agent displayed?
{O}
note: use your useless imagination and pretend these are square brackets
What is a reduction reaction
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
What is a polymerization reaction
when a very large amount of reactant molecules react together to form one very large product molecule
What are the ways in which a covalent bond can break
Heterolytic fission
homolytic fission
What is homolytic fission
the breaking of a covalent bond where each of the bonding electrons leaves with one species, forming a free radical
What is heterolytic fission
the breaking of a con=valent bond so that both bonding electrons are taken by one atom
forms a positive and negative ion
Definition of free radical????
a species that contains an unpaired electron
Definition of electrophile
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-
Definition of electrophile
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-
What is a hazard
something that could cause harm to to a user due to the inherit properties of the substances
What is a risk
the chance of a hazard causing harm
What is the meaning of a health hazard symbol
warning on skin rashes, eye damage and indigestion
what is the meaning of the corrosive symbol
causes skin burns and permanent eye damage
what is the meaning of the flammable symbol
can catch fire if heated or comes into contact with a flame
what is the meaning of the acute toxicity symbol
can cause life-threatening effects, even in small quantities
What apparatus can be used rather than a mercury thermometer
spirit thermometer or digital thermometer
What apparatus can be used rather than a tripod, gauze, and Bunsen burner
electrical heating mantle or (more likely) warm water bath
What can be used rather than connecting glass tubing with corks and rubber bungs
connecting by ground glass joints as it does not involve the risk of assembling the apparatus
What are the main processes needed to convert crude oil into fuel
fractional distillation
cracking
reforming
How does fractional distillation take place
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.
What is the difference between the molecules at the top of the column and the bottom
larger molecules, longer chains and higher b.p
What is the process of cracking
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
What is reforming
the conversion of straight-chained hydrocarbons into branched chain and cyclic hydrocarbons along with hydrogen as a useful by-product
What pollutants are emitted during the combustion of alkane fuels
carbon monoxide, oxides or sulfur, nitrogen, carbon particulates, and unburned hydrocarbons
Dangers of carbon monoxide
toxic gas that acts by prevents the transport of oxygen around the body. It is colorless and odorless
Dangers of oxides of sulfur and oxides of nitrogen
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
What can be used to reduce the amounts of pollutants
catalytic converters
How do catalytic converters work?????
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.
