PERCENTAGE ERRORS..for buretts and other stuff!!!!!..PLEASE HELP ME!!!!!!!!!!!!?

hi guys...well my dilemma is that i NEED TO WORK OUT THE PERCENTAGE ERRORS.....well , firstly the minimum error for a burette is 0.05 so, eg. (0.05/50mL x 100 = 0.1)...ok thats the begining...but i have also found somewhere that... "when you use a burette you take a reading at the start and the end , so you... show more hi guys...well my dilemma is that i NEED TO WORK OUT THE PERCENTAGE ERRORS.....well , firstly the minimum error for a burette is 0.05 so, eg. (0.05/50mL x 100 = 0.1)...ok thats the begining...but i have also found somewhere that...

"when you use a burette you take a reading at the start and the end , so you have two errors of 0.05 cm3 i.e. total error = 0.10 cm3. If you are using your burette to do a titration there may be another error of one or two drops which is due to your judgement of when the indicator changes colour. This means that in a titration (as opposed to just using a burette to measure a volume) you may have an error of 0.2 cm3."

so...(0.2/watever measurement x100)...BUT..in my past courseworks..i divided (0.05/ measurement x 100)..and i REALLY DO NOT KNOW WHICH ONE IS RIGHT???

i dont know whether i shud do % errors for every repeated experiment i have dne for that 1 test??or just for one...i just dont know which error to USE 0.05 or 0.2 AARGH!!! PLZ HELP ME !!?
Update: HEY BEAUTIFULNESS FAIRY.....that is EXACTLY WAT I MEAN..BUT what it is ..i'm doing titration with a pH meter...so i actually have something like 15 readings for ONE concentration...so...like u said about finding the average...dose that mean i have to do it for every single 15 results i have taken...PLUS the... show more HEY BEAUTIFULNESS FAIRY.....that is EXACTLY WAT I MEAN..BUT what it is ..i'm doing titration with a pH meter...so i actually have something like 15 readings for ONE concentration...so...like u said about finding the average...dose that mean i have to do it for every single 15 results i have taken...PLUS the repeated ones too??



eg. for conc 1.00mol i have



rough:11.0, 11.2, 11.6 ,......

trial 1: 11.2, 11.5,........(13/15 MORE results for all of them...)

trial 2:11.2, 11.5...........

trial 3: 11.1 , 11.4............
Update 2: HEY BEAUTIFULNESS FAIRY.....that is EXACTLY WAT I MEAN..BUT what it is ..i'm doing titration with a pH meter...so i actually have something like 15 readings for ONE concentration...so...like u said about finding the average...dose that mean i have to do it for every single 15 results i have taken...PLUS the... show more HEY BEAUTIFULNESS FAIRY.....that is EXACTLY WAT I MEAN..BUT what it is ..i'm doing titration with a pH meter...so i actually have something like 15 readings for ONE concentration...so...like u said about finding the average...dose that mean i have to do it for every single 15 results i have taken...PLUS the repeated ones too??

eg. for conc 1.00mol i have

rough:11.0, 11.2, 11.6 ,......

trial 1: 11.2, 11.5,........(13/15 MORE results for all of them...)

trial 2:11.2, 11.5...........

trial 3: 11.1 , 11.4............

SO...can u help me out a little...plzzz...i have soo mny results dose it mean i have to do it 4 EVERY SINGLE ONE OF THEM???..helllppp!!! pretty please??..
4 answers 4