oxidation and reduction (everything)

oxidation

occurs when the element loses electrons

reduction

occurs when the element gains electrons

redox reaction

one element loses electrons, another element gains electrons

reducing agent

element that loses the electrons

oxidising agent

element gaining electrons

are oxidising agents reduced or oxidized

reduced

are reducing agents oxidised or reduced

oxidized

oxidation numbers

charge an element has or appears to have when it is in a compound with certain rules applied

simple elements (not with any other element) have what charge

0

in the combined state, group one and group two elements have what charge

+1 / +2

charge of simple ions (single element ions)

equal to the charge of the ion

halogens in compounds where halogen is bonded to ONE other element

-1

halogen in compound where other element is more electronegative

+1

oxygen oxidation number

-2

oxygen oxidation number in peroxide ion

-1

oxygen oxidation number in compound OF2

+2

hydrogen oxidation number in compounds

+1

hydrogen oxidation number when bonded to an element less electronegative than itself

-1

complex ions oxidation number

add up to charge of ion

neutral molecules oxidation number

add up to 0

Sulphate ion

SO42-

Sulphite ion

SO32-

Nitrate ion

NO3-

Ammonium ion

NH4+

Dichromate VII ion

Cr2O72-

Manganate ion

MnO4-

Thiosulphate ion

S2O32-

Hyrdroxide ion

OH-

Hypochlorite ion

CLO-

Phosphate ion

PO43-

Peroxide ion

O22-

Hydrogen carbonate ion

HCO3-

Carbonate ion

CO32-

oxidation in terms of oxidation number

an increase in oxidation number

reduction in terms of oxidation numbers

reduction is a decrease in oxidation number

Define oxidation in terms of electron transfer.

loss