Acid bases and redox reactions

acid

releases H+ ions in a solution

base

proton (H+) acceptor

alkali

releases OH- ions in a solution as it dissolves

salt

formed when H+ in acid is replaced by a metal / ammonium ion (NH4+)

reaction of an acid and base ?

salt + water

reaction of an acid and metal

salt + hydrogen

word equation reaction for an acid and carbonate ?

salt + water + carbon dioxide

word equation reaction for an acid and alkali

salt + water

what happens when ammonia is dissolved in water and why ?

ammonia is a base as it accepts H+ ions . as it dissolves in water its OH- and NH4+ ions are produced making an alkaline solution

what can aqueous ammonia also be called ?

ammonium hydroxide

oxidation number of hydrogen ?

+1 except for when bonded to a metal as a hydride e.g. NaH - here its oxidation num is -1

oxidation number of oxygen ?

+2 except when in a peroxide e.g. H2O2 where its -1 instead

oxidation number of fluorine ?

always -1

oxidation number of metals ?

positive and usually the same as their group number

transition metals are positive but can have varying oxidation numbers

oxidation numbers of non metals ?

neg w/ values up to their grp number

how do you name compounds containing an element that doesn’t always have the same oxidation number ?

the oxidation number is shown as a roman numeral as part of the compound e.g. copper (II) sulphate

redox reaction

reaction where both reduction and oxidation take place

reduction

loss of oxygen

gain of electrons

addition of H

dec in oxidation num

oxidation

gain of oxygen

loss of electrons

loss of H

inc in oxidation num

oxidising agent

oxidise other species

accept electrons

are themselves reduced

reducing agents

reduce other species

donate electrons

are themselves oxidised