Why would I have to repeat titration 3 times in an experiment?

Question

I tried it 2 times and got the same answer each time.

Answer 1

To provide a statiscally valid answer. What is reported in chemistry and in many other sciences is an average value. In principle, the more times an experiment is done, the more reliable the answer becomes. So a minimum of three trials is needed to have a reliable answer that statiscally means something and it is not just an artifact of a simple average between two values. Also a third value, if you are doing a graph, ensures that you do indeed have a straight line, because, two points in space define a straight line, to really see whether or not is a true straight line that relates to a chemical or physical process, the third point is extremely important.

Answer 2

experiments fluctuate on many uncontrollable factors so the reason you repeat it at least 3 times is so you can average it and see how different your answers are from the average. even though you got the "same answer" each time, you probably didn't get the exact same answer depending how how exact your measurement is.

basically, your experiment is meant to come out to the same number because this is probably for a class and the experiment is meant to be foolproof. however, when you are doing real experiments where the answer is not known, you need to make sure you are getting the right answer, the right accuracy and precision. your teacher is just trying to get you to learn experimental method properly.

Answer 3

Well, you are pretty consistent but in general, there is some variation from experiment to experiment and 3 is the minimum number of experiments so that we can come closer to a true value (the average of 3 results is likely to be closer to the true value than 1 or 2). This is statistics in action.

Answer 4

To make sure that the first time is not a fluke, and to average out the random error differences.

Answer 5

Dunno. It's good that you got the same answer for the first two titrations, though.