Organic Chemistry Flashcards
Molecular formula
Notation used to show the type and number of atoms in a molecule
Condensed structural formula
Notation used to show type and number of atoms in a molecule with groups of atoms written separately
Structural formula
Graphical representation of a molecule showing types, number of atoms and how they are bonded
Homologous series
A group of organic molecules from the same family of organic molecules that share the same general forum and have similar chemical properties
General formula of alkanes
CnH2n+2
Alkanes
Homologous series of hydrocarbons, characterised by having carbon atoms linked with single bonds. Suffix - ane.
Alkene general formula
CnH2n
Alkenes
Homologous series of hydrocarbons characterised by having carbon atoms linked with one or more double bonds. Suffix -ene.
Hydrocarbon
Molecules that contain only carbon and hydrocarbon atoms
Chemical properties of alkenes and alkanes
- Non-reactive with acids, alkalis, metals and water
- Low melting/boiling point - weak intermolecular forces
- Volatile
- Smelly
- Don’t conduct heat/electricty
- Combust easily
- Non-polar - won’t dissolve in water
Saturated
Every carbon atom has the maximum amount of atoms bonded to it. (Alkane)
Substitution reaction
When there is a saturated molecule (alkane), if another atom is to be added, one atom must be removed first. For this to occur, enough energy must be available to overcome the activation energy required to break the C-H bond.
Unsaturated molecules
Not every carbon atom has the maximum amount of atoms bonded to it because of one or more double bonds. (alkenes)
Addition reactions
When there is an unsaturated molecule (alkene), if another atom is added, the double bond can be broken into a single bond and the available site is occupied by another atom. Requires less energy to break a double bond than a C-H bond so it can proceed more easily that a substitution reaction.
Alcohols
Homologous series characterised by having the -OH functional group hydroxyl.
Solute
The solid substance being dissolved
Solvent
The liquid that dissolves the solute
Solution
When a solute dissolves in a solvent
Soluble
A substance that can dissolve in a solvent
Insoluble
A substance that cannot dissolve in a solvent
Miscible
Two liquids that can dissolve into each other
Immiscible
Two liquids that cannot dissolve into each other
Complete combustion
Occurs in a plentiful supply of oxygen. All carbon and hydrogen atoms are oxidised to carbon dioxide (CO2) and water (H2O)
Incomplete combustion
Occurs in a limited supply of oxygen. Hydrogen atoms are oxidised to water (H2O) and carbo products include carbon monoxide (CO) and carbon/soot (C)
Non renewable fuel
Fuels that cannot be easily made or renewed. We can use up or exhaust non-renewable fuels eg oil, natural gas, coal etc
Carbon neutral
Making no difference to the amount of carbon dioxide in the atmosphere
Renewable fuel
A range of sources for generating energy which will always be available or are able to be regrown or remade
Fossil fuel
A natural fuel in the geological past from the remains of living organisms
Global warming
An increase in the temperature of earths’s atmosphere, generally attributed to increased levels of carbon dioxide (which traps heat) in the atmosphere.
Acid rain
Rainfall is made acidic by the effects of atmospheric pollution caused by burning fossil fuels
Ocean acidification
Name given to the ongoing decrease in the pH of the Earth’s oceans, caused by their uptake of carbon dioxide from the atmosphere.
Fractional distillation
The process in which various hydrocarbon components of crude oil are separated into fractions based on their different boiling points.
Cracking
Breaking long-chained molecules into shorter and more useful products such as petrol that can be made into plastics. Involves heat and a catalyst. Uses one alkane and one alkene.
Monomer
Small molecules (alkenes) which join to form polymers
Polymerisation
Joining a large number of small molecules to make a very long chain
Atomic structure of carbon
(2,4), 6 protons, 6 neutrons, 6 electrons, covalent bonding
General formula for alkanes
CnH2n+2
General formula for alkenes
CnH2n
General formula for alcohols
C(n)H(2n+1)OH
What is crude oil?
A mixture of hydrocarbons
Conditions required for cracking
Heat, pressure and catalyst
Conditions required for polymerisation
Heat, temp, catalyst, pressure