Help needed.

[fatimarehman]

Please can some one please tell me how to accurately record the time with stopwatch. I think I have forgotten and that's why I got percentage variation in k greater than 100 due to wrong time. Thanks in advance.

 

[muhammadali233]

the stop watch will give you the time(when in seconds) to 2d.p but you have to write it in 1 d.p because an avg human cannot be that precise.e.g the stopwatch shows 0:12.28 that means 12.28 seconds but in the table you will right it as 12.2,although 12.28 is acceptable but i won't recommend it as the graph will be very troublesome to make.
The point you need to remember is when the examiner ask to write T(time) T^2 or underroot T the answer should also be in 3 sig fig or 4 sig fig as per your value in the table (because 12.2 is 3sigfig and 12.28 is 4 sig fig).
<--- you will get something similar to this

 

[fatimarehman]

Does anyone has any guesses about the chemistry 33 practical. Please let me know.