Module 4 Chapter 11 Flashcards
Why is carbon the basis for all organic molecules (1)
Carbons easily form chains and rings because they form strong bonds with other carbon atoms.
Why is carbon the basis for all organic molecules (2)
They also form covalent bonds with atoms of other elements such as oxygen, nitrogen, hydrogen and the halogens
Why is carbon the basis for all organic molecules (3)
Carbon atoms form four links with other atoms. And this allows more atoms to be attached to the chains and rings so that the branches and other groups can be added.
What types of bonds can carbon form
Carbon atoms can form single, double or triple bonds.
How many electrons are involved in the 3 different types of covalent bonds
One shared pair of electrons = single bond
Two shared pairs of electrons = double bond
Three shared pairs of electrons = triple bond
What is the empirical formula
The simplest whole number ratio of the number of atoms in each element in a compound
What is the molecular formula
The actual number of atoms of each element in a compound
What is a displayed formula
Shows the order in which atoms are bonded (must show every bond). It also shows the relative positions of all atoms in a molecule and bonds between them.
What is a structural formula
Shows the minimal detail that shows the arrangement of atoms in a molecule.
What is skeletal formula
Shows a line for each bond but no carbon atoms or hydrogens next to carbons are shown. All other atoms are shown.
What are hydrocarbons (and examples)
They are compounds containing carbon and hydrogen only. They include alkanes, cycloalkanes, alkenes and arenas.
What does crude oil consist of
Crude oil consists of lots of hydrocarbons
What are cycloalkanes
Are alkanes where the two ends are joined to make a ring
What are Arenes
They are an organic molecule that contains one or more benzene ring in which 6 carbon atoms are joined in a ring.
Each carbon atom is only joined to three other atoms so each carbon has one outer shell electron left over.
What do these delocalised electrons do
They are shared between all 6 carbon atoms to make a delocalised pool of electrons shown by the circle in the middle of the ring.
What is a ring with delocalised electrons like this called
An aromatic ring
What does a benzene ring look like
DRAW IT
What is an aromatic compound
A compound containing a benzene ring
What are aliphatic hydrocarbons
Containing carbon atoms joined together in unbranched (straight) or branched chains and are not aromatic
What are alicyclic hydrocarbons
Contain carbon atoms joined together in a ring that is not aromatic
What is a saturated hydrocarbon
A hydrocarbons that only has single bonds only. No further atoms can be added to the molecule without removing one of the atoms already there.
What is an unsaturated hydrocarbon
Contains carbon to carbon multiple bonds (double or triple bonds), the spare electrons in the multiple bond can be used to add more atoms to the molecule.
What is the general formula
The simplest algebraic formula of a member of a homologous series
What is a functional group
A group of atoms responsible for the characteristic reactions of a compound
What is a homologous series
Is a series of organic compounds having the same functional group with each successive member differing by CH2
What do all the members of a homologous series have
Similar chemical properties
The same general molecular formula
What changes in a homologous series
The physical properties gradually change as the number of carbon atoms increases.
When are commas and dashes used
Commas between numbers and dashes between numbers and letters
What are structural isomers
They have the same molecular formula but a different structural formula.
What are positional isomers
For compounds that contain a functional group, this can be positioned at different positions along the carbon chain.
What can molecules sometimes have (functional groups and molecular formula)
Sometimes 2 molecules contain different functional groups, but have 2 different structural formulas but the same molecular formula.
What does a basic chemical reaction show us and what does it not show us
The reactants, the products and the stoichometry, however it doesn’t tell us how a reaction takes place.
What are curly double headed arrows used to show
The movement of a pair of electrons when bonds are broken or made.
What can covalent bonds be broken by
The shared pairs of electrons between a toms can be broken by either homolytic or heterolytic fission.
What is homolytic fission
where each of the bonded atoms takes one of the shared pair of electrons from the bond
Each atom now has a single unpaired electron
What is a radical
An atom or group of atoms with a single unpaired electron = radical
What is used to symbolise a radical
A dot is placed next to the atom or molecule
Draw the homolytic fission of a c-c bond in ethane
What occurs in heterolytic fission
The covalent bond breaks
One of the atom takes both of the electrons from the bond
The atom that takes both electrons becomes a negatively charged ion
The atom that doesn’t take the electrons becomes a positively charged ion
What is shown in a mechanism and how is it represented
The movement of electrons
This is shown using curly arrows
A half arrow represents the movement of a single unpaired electron
A full arrow represents the pair
Draw the mechanism for the homolytic fission of bromine
DRAW IT
Draw the heterolytic fission of H3C - CL
What is an addition reaction and an example and what breaks
Two reactants join together to form one product
E.g unsaturated alkene + water -> alcohol
The double bond breaks to form a saturated compound
What occurs in a substitution reaction
Atoms, or groups of atoms are replaced by a different atom or group
What occurs in elimination
Involves the removal of a small molecule from a larger one. One reactant forms two products.
