C4- Flashcards
which values are acidic
anything less than 7
what is a strong acid
An acid which completely ionises in aqueous solution
what do we call ions that arent involved in a chemical reaction
spectator ions
what is a base
a substance that can neutralise an acid
what PH values are alkaline
Any PH greater than 7
what ions do alkali form in water
OH−
is the ionisation of strong acids reversible
no it is not
whats oxidation in terms of electrons
oxidation is the loss of electrons
why should the electrodes be inert
So that they dont react with the electrolyte and dissolve away
which metals can be reduced with carbon(3)
Zibc
iron
copper
what is the general word equation for the reaction between an acid and a metal hydroxide
Acid + metal hydroxide –> salt + water
name 3 strong acids
HCL
nitric acid
sulphuric acid
what is reduction in terms of electrons
reduction is the gain of electrons
what ore is aluminum extracted from via electrolysis
bauxite
describe how metal ores can be reduced using carbon
- react the metal ore with carbon
- carbon will displace the metal as it is more reactive
what is the ionic equation for a neutralisation reaction
H +(aq) + OH −(aq) → H 2O(ℓ)
what is a weak acid?
An acid which only partially ionises in aqueous solution
what happens to positive ions during electrolysis
1, they are attracted to the cathode
2. they gain electrons
3.this means they have been reduced
why is cryolite used in the electrolysis of aluminium oxide
aluminum oxide has a very high melting point so it would be very expensive to melt
cryolite lowers the melting point which reduces the cost of the process
in electrolysis which two ions are present from the water molecules
h+ ions and OH- ions
what is a good indicator to use for titration between a strong and weak acid
Methyl orange
what is the general formula for a reaction between an acid and a metal carbonate
acid + metal carbonate –> salt water + carbon dioxide
general formula for a reaction between an acid and a metal
acid + metal –> salt + hydrogen
