Fuels + Heats of Reactions - Chp 21

Organic chemistry

is the study of the compounds of carbon

Hydrocarbon

is a compound that contains carbon and hydrogen only

Fossil fuels

fuels that were formed from the remains of plants and animals that lives millions of years agp

Saturated compound

is one in which there are only single bonds between the carbon atoms in the molecule

Which prefix is given to compounds with 1 carbon in its chain?

meth-

Which prefix is given to compounds with 2 carbons in its chain?

eth-

Which prefix is given to compounds with 3 carbons in its chain?

prop-

Which prefix is given to compounds with 4 carbons in its chain?

but-

Which prefix is given to compounds with 5 carbons in its chain?

pent-

Which prefix is given to compounds with 6 carbons in its chain?

hex-

What is the suffix for the Alkane family?

-ane

What is the suffix for the Alkene family?

-ene

What is the suffix for the Alkyne family?

-yne

What is the suffix for the Alcohol family?

-anol

What is the functional group for the Alkane family?

What is the functional group for the Alkene family?

What is the functional group for the Alkyne family?

What is the functional group for the Alcohol family?

Where is methanoic acid commonly found?

nettle + ant stings

Structural isomers

are compounds with the same molecular formula but different structural formulas

Homologous series

is defined as:

• a series of compounds of similar chemical properties
• showing gradations in physical properties
• having a general formula for its members
• each member having a similar method of preparation
• each member differing from the previous member by a (CH₂) unit

Primary alcohols

Have one carbon attached to the carbon attached to the OH group

Secondary alcohols

Have two carbons attached to the carbon attached to the OH group

Tertiary alcohols

Have three carbons attached to the carbon attached to the OH group

When is a carbon described as being planar?

when there is a double or triple bond between carbons

When is a carbon described as being tetrahedral?

when there is a single bond between carbons

Unsaturated compound

is one that contains one or more double or triple bonds between the carbon atoms in the molecule

Aliphatic compound

an organic compound that consists of open chains of carbon atoms and closed chain compounds (rings) that resemble them in chemical properties

Aromatic compounds

compounds that contain a benzene ring structure in their molecules

Auto ignition

Is premature ignition (explosion) of the petrol-air mixture before normal ignition of the mixture by a spark takes place

Octane number

Of a fuel is a measure of the tendency of the fuel to resist knocking

Catalytic cracking

Is the breaking down of long-chain hydrocarbon molecules by the action of heat and catalysts into short chain molecules for which there is greater demand

Heat of reaction

Is the heat change when the numbers of moles of reactants indicated in the balanced equation for the reaction to react completely

Heat of combustion

Of a substance is the heat change when one mole of the substance is completely burned in excess oxygen

Heat of formation

Of a compound is the heat of change that takes place when one mole of a compound in its standard state is formed from its elements in their standard states

Heat of neutralisation

Is the heat change when one mole of H+ ions from an acid reacts with one mole of OH- ions from a base

Bond energy

Is the average energy required to break one mole of a particular covalent bond and to separate the neutral atoms completely from each other

Kilogram calorific value

Of a fuel is the heat energy produced when 1kg of the fuel is completely burned in oxygen

Hess's law

states that is a chemical reaction takes place in a number of stages, the sum of the heat changes in the separate stages is equal to the heat change if the reaction is carried out in one stage

Describe the process of fractional distillation

• crude oil is heated in a furnace near the bottom of the fractionating column; this keeps the temperature high at the bottom

• hot vapour moves up along the column

• the temperature decreases as you ascend the tower

• as the crude oil rises up the tower, the fractions will reach a temperature that is just below their boiling point and turn into liquids which are collected in trays

• the heavier hydrocarbons will condense first, while the lighter hydrocarbons will rise higher and condense higher up the tower