chemical changes Flashcards
what is a spectator ion?
the ion which isn’t affected, this is purposely left out when writing half equations
what is oxidation?
when oxygen is added, leading to the loss of electrons
what is reduction?
when oxygen is removed, leading to a gain in electrons
what is a redox reaction?
where reduction and oxidation occurs in the same equation at the same time
what is an ore?
a rock containing enough metal viable to extract
how do we extract metals from ores?
if the metal is less reactive the carbon, then we can extract it by using carbon (react it with carbon, redox, displacement reaction), but if more reactive than carbon we use electrolysis
REMEMBER BAWS AND MASH
base + acid -> salt + water, metal + acid -> salt + hydrogen
what is an anion and cation?
an anion is a negatively charged ion which is attracted to the positively charged anode, a cation is a positively charged ion which is attracted to the negatively charged cathode. (PANIC - and they go in pairs AA and CC)
key info :
metal ions are always positively charged - cations
what happens to the differently charged ions at the electrodes?
negatively charged anions go to the positively charged anode and get oxidised, positively charged cations go to the negatively charged cathode and get reduced. *what happens matches the charge of the ion. +=gained
how can you remember the reactivity series?
please stop loudly calling my cat a zebra, I think lions can suck gorilla’s penises.
what is the reactivity series
potassium, sodium, lithium, calcium, magnesium, carbon, aluminium, zinc, iron, tin, lead, copper, silver, gold, platinum.
does an acidic solution contain more or less hydrogen ions
more ( ph1 has x10 power of 1 more than ph2 and x10 power of 2 more than ph3)
what is meant by the concentration of an acid?
the number of mole of acid dissolved in a set volume
determine strong acid
an acid where most or all hydrogen ion have fully dissociated, ph will be lower
determine weak acid
part, not many or no hydrogen ions have dissociated, ph will be higher
what do you have to consider when electrolysing a solution?
if the cations are less reactive than hydrogen and if the anions are halogens
if hydroxide is oxidised at the positive anode, what is formed?
oxygen and water
what is electrolysis?
the splitting up of electrolytes using electricity
