topic 3 chemical changes Flashcards
what ions do acids form
H+ ions
what is a base
a substance that reacts with an acid to produce a salt and water
what ions do alkalis form
OH- ions
what colour is litmus in different pHs
red in acidic, purple in neutral, blue in alkaline
what colour is methyl orange in different pHs
red in acidic and yellow in nuetral and alkaline solutions
what colour is phenolphthalein in different pHs
colourless in acidic or neutral, pink in alkaline
what is a neutralisation reaction
a reaction between a base and an acid
what is produced in a reaction between an acid and a metal oxide
salt and water
what is produced in the reaction between acid and metal hydroxide
salt and water
what is produced in a rection between an acid and a metal
salt and hydrogen
what is produced in the reaction between an acid and a metal carbonate
salt, water and carbon dioxide
what is produced in the reaction between an acid and a metal carbonate
salt, water and carbon dioxide
is common salts of sodium, potassium and ammonium soluble or insoluble
soluble
are nitrates soluble or insoluble
soluble
are common chlorides soluble or insoluble
soluble, except silver chloride and lead chloride
are common sulfates soluble or insoluble
soluble except lead, barium and calcium sulfate
are common carbonates and hydroxides soluble or insoluble
insoluble, except for sodium, potassium and ammonium ones
how do you make a pure, dry sample of an insoluble salt
pick two soluble salts and mix them together
how do you make a soluble salt
by reacting an acid that contains one of the ions that you want in the salt with an insoluble bas that contains the other ion you need
what is electrolysis
the breaking down of a substance using electricity, an electric current is passed through an electrolyte causing it to decompose
what is an electrolyte
a molten or dissolved ionic compound
what is an electrochemical cell
a circuit, made up of the anode, cathode, electrolyte, a power source and the wires that connect the two electrodes
how do you set up an electrochemical cell if your electrolyte is a solution
clean the surfaces of to inert electrodes using emery paper, place into a beaker filled with the electrolyte, connect the electrodes to a power supply
how do you set up an electrochemical cell if your electrolyte is a molten ionic substance
put the solid in a crucible and heat until molten in a fume cupboard, dip two clean inert electrodes into the electrolyte and connect to a power supply
at which electrode does oxidation happen in electrolysis
the anode
