moles 2 Flashcards
how to convert from dm3 to cm3?
x1000
how to convert from cm3 to dm3?
/1000
how to calculate moles? (volume and 24)
moles= volume/24
what is the concentration of a solution?
a measure of how much solute is dissolved per unit volume
what is concentration measured in?
mol/dm3
formula for concentration?
moles/volume
formula for moles? (concentration and volume)
moles = concentration x volume
what is titration used to measure?
the volume (titre) of acid needed to neutralise a particular volume of alkali
what 2 pieces of equipment do you need for titration?
- volumetric pipette
- burette
what does a volumetric pipette do?
- measures out 25cm3 very accurately
what does a burette do?
measures any volume to the nearest 0.05cm3
where does the acid and alkali go?
- acid goes into the burette
- alkali goes into the conical flask
what is the setup for titration? (3 steps)
- use a volumetric pipette to place 25cm3 of the alkali into a conical flask
- add a few drops of methyl orange/ phenolphthalein to the conical flask
- fill a burette with a known acid and clamp it above the conical flask
what is the usage of titration? (6 steps)
- measure the initial volume of the acid in the burette, to the nearest 0.05cm3
- use the burette to add acid into the conical flask drop-by-drop and keep swirling the conical flask
-close the burette tap as soon as the conical flask changes colour - measure the final volume of the known acid on the burette to the nearest 0.05cm3
- calculate titre (final volume- initial volume)
- repeat to get concordant values
what will the start and end colour of titration be?
- start colour will be the alkaline
- end colour will be the acidic
