chemical changes Flashcards
what is a metal oxide
when a metal reacts with oxygen and a visible reaction takes place
what is an oxidation reaction what is the word equation for this
a reaction that is gaining oxygen
metal + oxygen = metal oxide
what is a reduction reaction what is the word equation for this
a reaction that is loosing oxygen
metal oxide = metal + oxygen
what is the reactivity series and how do we create this
a way to compare the metals reactivity
- they need to be reacted with water and acids to see how fast or violent a reaction is
roughly draw an example of the reactivity scale
group one |as you go down metals become
| less reactive. the temperature
| change also measured
group two | only group one metals are
| reactive enough to react
transition | with water
metals | transition metals don’t react
with acid
what are displacement reactions
more reactive metals can displace less reactive metals
how are most metals found when extracted
as metal oxides
how are metal oxides reduced to get pure metals
react metal oxide with carbon to form
CO2 + pure metal
OR electrolysis
which element would be reduced and what would be oxidised
CO2 oxidised
pure metal reduced
what is the problem with the carbon method of reducing metal oxides
doesn’t work with all metals, only those less reactive than carbon
what is meant by the oxidation of electrons
oxidation = loss of electrons
reduction = gain of electrons
what are the equations for reactions between acids and metals
acid + metal - salt + hydrogen gas
when hydrochloric acid is used the ending is -chloride
when sulfuric acid acid is used the ending is
- sulphate
what happens when magnesium, zinc and iron react with acid
magnesium - rapidly with acid
zinc - reacts quite rapid with acid
iron - reacts fairly slow with acid
what is the equation for the reaction between metal oxides and acid
metal oxide/hydroxide + acid — salt + water
what is the equation for the reaction between carbonates and acid
metal carbonate + acid —salt + water + CO2
