1. Density Lab

2. Warm - Up What is density? What is the formula for density?
What are some different methods that we could use to find the density of a solid object?

3. Objective Today I will be able to:
Apply the formula for density to problem solving
Calculate density by using different laboratory techniques

4. Homework
Turn In: Dimensional Analysis HW
Density practice problems

5. Agenda Warm – Up Density Notes Density Lab Density practice problems
Exit Ticket

6. Types of Statistical Tests
Paired T-Test
Unpaired T-Test
ANOVA
Chi-Square
Coefficient of Correlation

7. T-Tests
This test is used to compare the data from two different testing groups to determine if they are significantly different. There are two different types:
PAIRED: Used when the data consist of pairs of observations on the same person or object.
Example: comparing the heart rate of individuals before and after watching a scary movie.
UNPAIRED: Used when the data from one group are not directly linked to the data of the other group.
Example: comparing the effect of red light versus blue light on the growth of plants.

8. ANOVA
This test is used to determine whether there are any significant differences between the means of three or more independent (unrelated) groups.
Example: determining whether exam performance differed based on test anxiety levels amongst students. Students are divided into three independent groups (e.g., low, medium and high-stressed students).

9. Chi-Square Test
This test is used to determine if there are differences between two or more frequency distributions. Both independent and dependent variables need to be categorical data.
Example: comparing the foraging height (upper, middle, and lower) of yellow warblers in different tree species (oak, maple, aspen, and hazel).

10. Analyzing the Test Results
Two possible conclusions after carrying out a test
Hypothesis supported
Hypothesis not supported

11. Analyzing the Test Results (cont.)
P-values : one way to report the result of an analysis is by saying whether or not the hypothesis was rejected at a specified level of significance (we will use .05)
The smaller the calculated p-value, the greater the difference between the groups.
Example: the difference in means from our testing groups is statistically significant at the .05

13. Discuss with a partner
What type of statistical test should I use to analyze my data?

14. STEM Fair Data Collection and Analysis Due: October 10
Mr. Klotz’s Expectations:
Data Tables
Appropriate Graphs
Complete Statistical Analysis Worksheet and Place in the Folder

15. Density Notes

16. What is the formula for density?

17. Density = Mass Volume

18. What are the units for density?

19. Solid - g/cm3 Liquid – g/ml

20. What is density… more specifically
Physical Property
Density reveals how tightly the molecules composing the matter are packed and how heavy the molecules are
Compared to the liquid they are in, less dense materials float, more dense sink
Substances are often IDed by their density, as it is rare for two substances to have the same density

21. Density and States of Matter
Solids – composed of tightly packed molecules, low kinetic energy, high density (Iron)

22. Density and States of Matter
Liquids – more loosely packed than solids, density less than solids (water)

23. Density and States of Matter
Gases – molecules are all over the place, density less than solids and liquids (air)

24. How to Calculate Density
Mass is determined using a scale
Volume is calculated several different ways

25. Finding Volume
To find the volume of a liquid, use a graduated cylinder
Make sure to read the bottom of the meniscus

26. Finding Volume Length x Width x Height
Volume of a regular object, such as a wooden block

27. Finding Volume Water Displacement Method
- Read the initial volume of water in a graduated cylinder
- Place object into cylinder
- Read the final volume of water
- Final – Initial = Volume of the object

28. Odd Shaped Marble Lab
Complete the density lab at your desk, when you finish complete the density calculations practice

29. Density Calculation Practice
Complete the calculations at your desk. Calculations not completed in class will be completed for HW

30. Exit Ticket
Write the density of water that you calculated in parts A and C on the board in the appropriate column.
Why do we see variation? What could be the source?
Which method of calculating density is most precise?

31. Exit Ticket: Think about the densities of the following substances
Exit Ticket: Think about the densities of the following substances. Use the density to answer the following questions.
A. Lead B. Feathers

32. Which has a greater mass, 6.00 g of lead or 7.00 g of feathers?
A. Lead B. Feathers
feathers

33. Which occupies a greater volume, 5. 00 cm3 of lead or 5
Which occupies a greater volume, 5.00 cm3 of lead or 5.00 cm3 of feathers?
A. Lead B. Feathers
neither

34. Which occupies a greater volume, 5.00 g of lead or 5.00 g of feathers?
A. Lead B. Feathers
feathers

35. Which occupies a greater volume, 9.00 g of lead or 50.0 g of feathers?
A. Lead B. Feathers
feathers

36. Which occupies a greater volume, 50.0 g of lead or 9.00 g of feathers?
A. Lead B. Feathers
Not enough information to determine