Unit 2- Mechanisms Flashcards
1
Q
What is an oxidation reaction?
A
- Loss of electrons
- Add of oxygen
- Removal of hydrogen
- Increase in oxidation number
2
Q
What is a reduction reaction?
A
- Gain of electrons
- Addition of hydrogen
- removal of oxygen
- decrease in oxidation number
3
Q
What is homolytic fission?
A
- In a covalent bond, shared pair of electrons between two atoms
- When the covalent bond breaks, both atoms get one electron
- Forms a free radical
4
Q
What is heterolytic fission?
A
- Covalent bonds involve the sharing of a pair of electorns
- When the bond breaks, one atom involved in the covalent bond recieves both electrons
- generally occurs iin polar solvents e.g. water
- Characteristic of polar bonds therefore more likely with atoms of high electronegativitiy
- Greater electronegativity leads to a pull in electrons therefore when the bonds break, one atom takes both
5
Q
What is a substitution reaction?
A
- When an atom or group of atom replaces an ato or group of atoms
- e.g free radical substitution
6
Q
What is an addition reaction?
A
- The addition of one molecule to another to form one molecule
- normally involves an alkene due to the double bond
7
Q
What is a hydrolysis reaction?
A
- The splitting of a molecule involving water
8
Q
What is an elimination reaction?
A
- When a molecule is split to form two molecules
- One of the molecules would normally have a double bond
9
Q
What is a polymerisation reaction?
A
- Small molecules with double bonds join to form long chain of a polymer
- Can involve addition polymers
10
Q
What is a free radical?
A
- A species with an unpaired electron
- Highly reactive
11
Q
What is a nucleophile?
A
- A species that attacks a positive nucleus/atom
- Normally negative e.g. OH
12
Q
What is an electrophile?
A
- A species which attatcks a negative rich area
- Can accept electrons
13
Q
A
