[appleseed]

ok say im measuring enthalpy change for one exo and one endothermic reaction.
the equipemnt i use are:
thermometer (+/- 0.5)
electric balance (for measuring weight of solid) (+/- 0.1)
measuring cylinder  (+/- 0.5) 

ok so i have to measure the inital temp and final temp and find the difference to get the temperature change so the total uncertainty for themometer is (+/- 1.0)


ok, stay with me,


say these are my results: endothermic reaction- temp change= 5 (+/- 1.0)  the mass of chemical used was 30g and the vol of chemical used was 10ml
exothermic reaction - tempchange= 2 (+/- 1.0)  the mass of chemical used was 40g and the vol of chemical used was 5ml

so if i was to calculate the percentage error of the thermometer i would do (uncertainty/ smallest reading)x100%. and since the smallest reading is 2 then :
(1/2)*100%=+/-50%

OR IS IT?:

(0.5/2)*100%= 025%


an i right?

[sjb]

so if i was to calculate the percentage error of the thermometer i would do (uncertainty/ smallest reading)x100%. and since the smallest reading is 2 then :
(1/2)*100%=+/-50%

This is the way I'd do it...