1. Quantitative Properties For Matter
08/27/15

2. Reminders
Quiz Monday
You will use this information for tomorrow’s performance-based density lab

3. Agenda Define density How to measure Significant figures
Scientific notation
Accuracy vs precision
*metric system*

4. Wrap-Up: Density
Formula?
Definition?

5. Wrap-Up: Density

6. Wrap-Up: Density

7. Agenda Define density How to measure Significant figures
Scientific notation
Accuracy vs precision
*metric system*

8. How do you measure? We want the best measurement possible.
Electronic scale  use all the digits given
You read yourself  use what’s given + estimated digit
Glassware such as graduated cylinder, beaker, etc
Measuring devices such as rulers, meter sticks, etc

9. Estimated digit

10. Estimated digit

11. Estimated digit

12. Agenda Define density How to measure Significant figures
Scientific notation
Accuracy vs precision
*metric system*

13. Significant figures – the “important” numbers
Abbreviated as “sig figs”
When should you round the final answer?

14. Significant figures – the “important” numbers
The # of digits your final answer contains should be the same amount as the given with the lowest # of digits
5.5, 4.55, 
5.5, 4, 
Only as strong as your weakest link

15. Do you know your rounding rules?
0-4 rounds…..
5-9 rounds….

16. Sig figs – rules!
There are rules for which numbers are significant (not all #s are important!)
Easiest way to remember: the Pacific/Atlantic rule

17. PA rule – cross out all zeros depending on decimal

18. Sig figs - practice
What is the density of an object with a mass of 12.0 g and a volume of 3 mL?
What is the density of an object with a mass of 12.0 g and a volume of 6.0 mL?
What is the density of an object with a mass of 10.0 g and a volume of 0.50 mL?
What is the density of an object with a mass of 0.5 g and a volume of 0.05 mL?
What is the density of an object with a mass of g and a volume of 50.0 mL?
What is the area of an object with a length of 50 cm and a width of 10 cm?

19. Agenda Define density How to measure Significant figures
Scientific notation
Accuracy vs precision
*metric system*

20. Scientific notation #.# x 10# Use exponents to replace digits
Start at decimal and move either forward or backward to get this formula:
#.# x 10#

21. #.# x 10# # the decimal is always moved to after this digit
# the number of these digits depends on how many sig figs you want
# this represents how many times you moved the decimal over
If you moved the decimal to the left, the digit should be negative (-)
If you moved the decimal to the right, the digit should be positive (+)

22. Scientific notation examples
Convert 3,000 to scientific notation using 2 sig figs
Convert 3050 to scientific notation using 2 sig figs
Convert 3040 to scientific notation using 2 sig figs
Convert to scientific notation using 2 sig figs

23. Scientific notation examples
Convert 3.45 x 102 to the decimal form using 2 sig figs
Convert x 10-3 to the decimal form using 3 sig figs

24. Agenda Define density How to measure Significant figures
Scientific notation
Accuracy vs precision
*metric system*

25. Accuracy vs Precision
Accuracy – how close your answer is to the true/accepted value (the answer)
Precision – how close your answers are together

27. Accepted value: 5.75 A B C
5.55
6.96
4.32
5.65
5.75
1.63
5.21
3.23

28. Agenda Define density How to measure Significant figures
Scientific notation
Accuracy vs precision
*metric system*

29. Metric System – largest to smallest
Kilo_________
Hecta ________
Deca ________
(Base) ________
Deci ________
Centi ________
Mili ________

30. Metric System – largest to smallest
Kilo_________
Hecta ________
Deca ________
(Base) ________
Deci ________
Centi ________
Mili ________
King
Henry
Died By
Drinking
Chocolate
Milk