1. Math Unit
The metric system, scientific notation, factor labeling and problem solving

2. 3 Warm-up Question Liberia Myanmar (formerly Burma)
The United States is one of how many countries in the world that still use the imperial system of measurement? What are the other countries? 3
Liberia
Myanmar
(formerly Burma)

3. Units of Measurement SI Units
a system of units of measurements devised around seven base units and the convenience of the number ten.

4. Units of Measurement
Metric System

5. Units of Measurement

6. Sample problem Convert the following Start with 53.
Move the decimal to the right
Move the decimal to the left
Convert the following
53 hg = ________dg
Start with 53.
Move the decimal 3 spaces to the right 53
Fill in the empty spaces with zeros dg

7. Sample Problem Start with 300.
Move the decimal to the right
Move the decimal to the left
Convert the following
300 cg = ________kg
Start with 300.
Move the decimal 5 spaces to the left
Fill in the empty spaces with zeros kg

8. Units of Measurement Examples… 1000 mg =__________ g
160 cm = __________ mm
109 g = __________ kg
1 L = __________ mL
14 km = __________ m 1
1600
0.109
1000
14000
Move the decimal to the right
Move the decimal to the left

9. Exit Question
Now that you are a metric master, would it be easier to convert inches to miles or centimeters to kilometer? Explain.

10. 602000000000000000000000 Warm-up Question It’s a mole!!!
What is the significance of this number?
It’s a mole!!!
(the SI unit for a amount of a substance)

11. Scientific Notation
Scientific notation expresses numbers as a multiple of two factors: a number between 1 and 10 (coefficient); and ten raised to a power, or exponent.
The exponent tells you how many times the first factor must be multiplied by 10.
When numbers larger than 1 are expressed in scientific notation, the power of 10 is positive.
When numbers smaller than 1 are expressed in scientific notation, the power of 10 is negative.
Exponent
6.02 𝑥
Coefficient

12. Scientific Notation
Examples…
Change the following data into scientific notation:
The diameter of the Sun is 1,392,000 km.
The density of the Sun’s lower atmosphere is g/cm3.
1.392 𝑥 km
2.8 𝑥 10 −8 g/cm3

13. Scientific Notation Adding and Subtracting Using Scientific Notation
The exponents must be the same before doing the arithmetic. Convert the smaller number to the bigger one, by moving the decimal to the right.
Add or subtract the coefficient.
Keep the exponent the same.
Make sure your answer is written in proper scientific notation.
Example…
1.26x104 kg + 2.5x103 kg = ____________________ kg
1.51x 104

14. Scientific Notation Multiplying and Dividing Using Scientific Notation
Multiply or divide the coefficients.
Add the exponents (for multiplication) or subtract the exponents (for division).
Examples…
(2x103 cm) x (3x102 cm) = ____________________ cm2
(9x108 g) ÷ (3x10-4 mL) = ____________________ g/mL
6 x 105
3 x 1012

15. Exit Question
Scientific notation should come in handy when expressing what kinds of quantities in chemistry?
Submicroscopic things like the size of an atom or the number of atoms in a substance.

16. Warm-up Question
How can you simplify this problem before you calculate the answer?
2 5 × 3 4 =

17. Dimensional Analysis (Factor Label)
A conversion factor is a ratio of equivalent values used to express the same quantity in different units.
A conversion factor is always equal to 𝑐𝑚 1 𝑚 = 1 𝑚 100 𝑐𝑚 = 1
Dimensional analysis is a method of problem-solving that focuses on the units used to describe matter.
Dimensional analysis often uses conversion factors.
When you convert from a large unit to a small unit, the value of the number must increase.
When you convert from a small unit to a large unit, the value of the number must decrease.

18. Factor Label Method of Conversion
100 cm = 1 m
1 m = 100 cm
Use conversion factors to systematically move from one unit to the next, cancelling out units on the diagonal in each step. Convert 18 m = _______ cm
100 cm
18m
= 1800 cm
1 m

19. Dimensional Analysis 24 hr 90 km 60min 60sec = 86400 sec 1 hr 1 min
Examples…
How many seconds are there in 24 hours?
A car is traveling 90.0 kilometers per hour. What is its speed in miles per minute?
60min
60sec
24 hr
= sec
1 hr
1 min
90 km
1 hr
0.62mi
1 hr
= 0.93 mi/min
1 km
60 min
1 km = 0.62 miles
1 hr = 60 mins
1 min = 60 secs

20. Exit Question How many fuggles are there in 19 blops?
On the planet Rigel, Rigellians have developed a system of measurements called S.U., or Systems Universal. Here is the conversion table for the measurements of distance:
1 gleem = 27 blops
1 blop = 34 riddigs
1 riddig = 42 chirks
1 chirk = 9 fuggles
10 fuggles = 52 hippers
2.5 hippers = 1.2 zookas
1 zooka = 7 wenzels
Use the Factor Label Method and the conversions above to solve the problem.
How many fuggles are there in 19 blops?  

21. Problem Solving
It is important to understand what you have, what you need and how you are going to get it.
Example
The mass of a brick of aluminum is 87 g. If the density of aluminum is 2.7 g/ml, what is the volume of the brick?
Have
Need
How
Mass=87g
Volume
V=M/D
Density = 2.7 g/mL
D=M/V