1. But Does it Have any Significance?

2. Title
Significant Figure Lab

3. Pre-Lab Questions What does ‘significant’ mean in every day language?
Do you need to write down every digit you see in your calculator after you perform a calculation?
How do you decide which digits are important enough to write down?

4. Purpose/Objective SAFETY!!
To define ‘significant’ as used in chemistry
To be able to determine whether digits are significant or not
SAFETY!!

5. Materials Paper with large rectangular figure Metric rulers
Metric measuring tape
Twine (1 m length)

9. Procedure
Measure and record each side of the rectangle with each measuring device provided
That’s it!

10. Data Measuring tool Length (in ?) Width (in ?) Ruler Flexible tape
Twine

11. Analysis Calculate the perimeter of the rectangle
Calculate the area of the rectangle
Report your findings to the class
Calculate the average perimeter and area from the class data

12. Class Data
Group
Perimeter (in ?)
Area (in ?)
1 ruler
tape
twine 2 3

13. Conclusion
Did some of the measurements have better agreement than others, i.e., were they closer to each other?
How many digits did you know FOR CERTAIN using each instrument?
How far apart were YOUR measurements from the class average?
Would it be wrong to record a measurement made with an ordinary ruler as cm? Explain.

14. How do you measure?

15. How do you measure?

16. Can we do better?

17. What about mass?

18. Mass again

19. And then there’s volume

20. Volume again

21. More volume

22. More volume

23. More volume
Microliters! Pricey!!