OCR A 2.1.5 Redox

reducing agent

lose electrons, oxidised themselves

oxidising agent

gain electrons, reduced themselves

reduction

decrease in oxidation number

oxidation

increase in oxidation number

oxidisation state of uncombine element

0

oxidisation state of ion

same as charge on ion

oxidisation state of grp 1

+1

oxidisation state of grp 2

+2

order which you assign oxidisation state

F, O, N, Cl

oxidisation state of H in metal hydride (NaH)

-1

oxidisation state of O in H₂O₂

-1

oxidisation state of transition elements

variable oxidation state; depends on other element in compound

how to name compound by systematic name

-shows oxidation number of element without sign

NO₂^- systematic name

nitrate(III)

as N has oxidation state of 3