1. Fraction style ratios Measurements & Sig Figs
Block 2
Fraction style ratios
Measurements & Sig Figs

2. Warm-Up Turn in all paper work to the tray
Put electronics in the boxes
Binder Setup
Tab 1: Reference Material
Add Syllabus, Bathroom Passes, Element List
Tab 2: Warm-up
Add 5 pieces of filler paper
Tab 3: Current Material
Tab 4: Learned Material

3. Website- bit.ly/bowiechemistry
Class blog, Tutoring
Bathroom passes

4. How to take A Quiz, Quiz
Two from every pair will move based on your desk letter
There are four open desks in the lab as well as 8 lab stations
Stand on the back side of the lab tables (labeled with stickies)
You will leave the quiz face down until everyone has one
Once time is started you may begin

5. ELEMENT QUIZ Everything off your desk Pen only
5 minutes to complete on your own

6. Using Conversion Factors
How many decimeters in 1 meter?
How many centigrams in 2 g?
( 10 𝑑𝑚 1 𝑚 )
𝟏 𝒎 𝟏𝟎 𝒅𝒎 𝐨𝐫 𝟏𝟎 𝒅𝒎 𝟏 𝒎
? dm =
1 m
= 10 dm
( 100 𝑐𝑔 1 𝑔 )
𝟏 𝒈 𝟏𝟎𝟎 𝒄𝒈 𝐨𝐫 𝟏𝟎𝟎 𝒄𝒈 𝟏 𝒈
? cg =
2 g
= 200 cg

7. Try it out!
A chemist ships a box of moles to Avagadro by mail. The box of moles cannot exceed a mass of 10 kg. If each mole masses and average of 136 g, how many moles will Avagadro receive?
1. What do you know?
1 mole = 136 g
1 box= 10 kg
2. What are you looking for?
Number of moles
3. Where do you start?
Shipping 1 box

8. Try it out! 1. What do you know? 2. What are you looking for?
1 mole = 136 g
1 box= 10 kg
2. What are you looking for?
Number of moles
3. Where do you start?
Shipping 1 box
( 10 𝑘𝑔 1 𝑏𝑜𝑥 )
( 𝑔 1 𝑘𝑔 )
( 1 𝑚𝑜𝑙𝑒 136 𝑔 )
? moles =
1 box
= 73.5 moles
𝟏 𝒃𝒐𝒙 𝟏𝟎 𝒌𝒈 𝐨𝐫 𝟏𝟎 𝒌𝒈 𝟏 𝒃𝒐𝒙
𝟏𝟎𝟎𝟎 𝒈 𝟏 𝒌𝒈 𝐨𝐫 𝟏 𝒌𝒈 𝟏𝟎𝟎𝟎 𝒈
𝟏𝟑𝟔𝒈 𝟏𝒎𝒐𝒍𝒆 𝐨𝐫 𝟏𝒎𝒐𝒍𝒆 𝟏𝟑𝟔 𝒈

9. Why are Chemists so good at solving problems?
Show all work on separate paper
Use CONVERSION FACTORS to solve
I do #1
We do #2
You do the rest through #7

10. Measurement What instruments do we use to measure metric units?
On pg 3 in your packet read the stated problem
Write your answer under “my thoughts” giving me your answer, why it is the right answer based on evidence, and your reasoning behind it

11. 2.10 teaspoons of Antihistimine

12. 2.10 teaspoons of Antihistimine
1 tsp=4.93 mL
600 mL Beaker
10 mL Test tube
1 L Erlenmeyer Flask
1 L Graduated Cylinder
10 mL Volumetric Pipette

13. LAB
The hospital is looking to buy new equipment for all the nurses. You will test each model item, collect and analyze data, and prepare a summary to the board on your product recommendation.
Mass the cup then fill it with 50 mL of water. Record mass and EXACT volume of water used.
Mass the beaker. Pour water from the cup into the beaker. Record mass and EXACT VOLUME transferred.
Determine the mass of water in each sample. Mass the grad cylinder. Pour water from the beaker into the cylinder. Record mass and EXACT VOLUME transferred.

14. Analysis Which pieces of equipment would you recommend and why?
Having trouble? Textbook pg 47-53

15. Instrumentation & Measurment
The more divisions of measurement the more EXACT we can be.
The more decimals (or significant figures) the more exact a measurement is
When is it important to have exact measurements?

16. Pg 3
Practice Sig Figs

17. Take Away Accuracy- how close a measured value is to an accepted value
Precision how close a series of measurements are to one another
Practice: The known mass of Cobalt is g/mol
58.9, 58.92, 59.0
50, 51, 45
62, 62.1, 62.0
Both accurate & precise
Not accurate or precise
Precise but not Accurate

18. How can we increase precision?
Increasing the numbers of significant digits!
Significant digit- all numbers in a measurement plus an extra for estimation.
6.60 mL
6.63 mL

19. Learning Check On a quarter sheet of paper write your name & period
Title: Learning Check- METRIC
Answer the following on your own
What instrument do we use to measure volume?
Write BOTH conversion factors for how many mm in a cm
______ Hg in 43.2 cg

20. Homework Content Covered
Finish Puzzle on page 2
Optional: Bathroom Pass Bingo supplies due 9/2 (next wed)
Fraction Style Ratios
Started Measurement Lab

21. ATOMIC THEORY FOLDABLE
With the paper horizontal, fold two flaps of equal size inward
Vertically fold paper into thirds. Open back up.
Cut along the horizontal folds on the FRONT FLAPS ONLY