evaluating accuracy and reliability (1 Viewer)

[angelargh]

hi
i was wondering if anyone could help me out here
evaluating ways in which the accuracy and reliability could be improved in investigations for precipitation pracs, titration and AAS
assessing validity of conclusions from precipitation prac and titration?
thanks!

 

[Shoom]

Reliability of an experiment can be found out, by repeating the particular experiment x amount of times.

Say for titration 1:12ml, titration 2: 27ml titration 3 : 6 ml, then the experimental data is not reliable since significant differences are recorded after titration.


Accuracy, at high school level is usually conductor induced ( aka not reading volumes of beakers,etc correctly, contamination, lab not being exactly STP)


Validity can be checked by making sure your data supports published data.

Like, say you conclude that HCL + NaOH ---> no reaction, but published ( credible science journals) say you get a salt and water, then obviously your experiments are not valid.

 

[Ishynooshy]

I agree with almost everything above, except for the accuracy. The way that accuracy is improved is by increasing the sensitivity to changes in measurement in equipment.

Eg. Using an electronic balance that can measure to 5dp is more accurate than one that has no decimal places. For the titration prac, I can say with 99% certainty that the burettes that you are using (or going to use) at Type B, which are of a lower accuracy than Type A burretes, which are used in research labs. If you were to use the type A burretes, then that would increase accuracy as well.