acids bases and salts

Question 1

how to prepare salt crystals

Answer 1

1: + excess carbonate/base to make sure all of the acid has reacted
(if you use a carbonate you will see fizzing/effervescence)
2:filter off the excess base / carbonate.
(this removes the unreacted carbonate /base )
3:heat in the evaporating dish /leave for a week .this ensures that all the water has evaporated there would also be a colour change if there was any copper (blue)

Question 2

tit rations

Answer 2

used to neutralise substances

Question 3

how does a titration work ?

Answer 3

so first you use a ppippe the rtransfer the alkali tot the conical flask then you add a feww drops of indicator
you place a white tile underneth the conicla flask to ensure that you are able to see the colourchange if any
then you add the acid to the burette one that has been done you do a trial run to have rough idea of how much acid is need to nutralise the alkali
then you do your first official run and you add the acid untill you see a colour change /.then you carefully add the acid drop by drop .you do this to ensure you dont over shooth the end point .als remember to carefully swirll the mixture so that they mix properly this is a type ogf nutralisation reaction

Question 4

what is another way that you can calculate the concentration in grams dm3

Answer 4

we take the concentration in mol/dm3 and multiplication it by mr

Question 5

what are the rules of predicting what will happen at the the anode

Answer 5

if a halide is present the halogen gas will be produced at the anode

if a halide is not present then the OH- ions will be attracted to the anode and oxygen gas will be produced

Question 6

what are the rules of predicting what will happen at the cathode

Answer 6

this depend on the reactivity of the metal

if they are more reactive than the hydrogen in the reactivity series hydrogen forms at the cathode

if they are less reactive than hydrogen in the reactivity series then the metal is formed at the cathode.