1. 11/29 Opener
How should you act when we have a substitute? What would proper movie etiquette look like?

2. 12/4 Opener
Convert 5 hm to mm

3. Conversions & Dimensional Analysis
SWBAT utilize appropriate conversion factors and dimensional analysis as strategies for solving problems that require different units

4. Conversion Factors
A conversion factor is a ratio of equivalent measurements.
Where the numerator (top number) is equal to the denominator (bottom number)
When a measurement is multiplied by a conversion factor the numerical value is changed by the size of the quantity remains unchanged.
Example conversion factors: 100𝑐𝑚 1𝑚 or 1𝑘𝑔 1000𝑔 where 100cm=1m and 1kg=1000g

5. Dimensional Analysis
Dimensional analysis is the way to analyze and solve problems using the units of a measurement.
Dimensional Analysis Steps:
Start with the given value and its units
Use a conversion factor that expresses the given units in the denominator (bottom) and wanted units in the numerator (top) this allows the given unit to be canceled out
Use additional conversion factors as needed to reach your final units
Multiply through the top and divide by the bottom numbers

6. Scientific Notation
In scientific notation a number is written as a product of two numbers: a coefficient and 10 raised to a power.
Example 602,000,000,000,000,000,000,000 is 6.02x1023 where the coefficient is and the power of 10 is raised to the exponent 23.
In scientific notation the coefficient is always greater than 1 and less than 10.

7. Practice Problem How many seconds are in an 8 hour workday? Known
Time Worked: 8 hours
1 hour = 60 minute
1 minute = 60 seconds
Unknown
Seconds worked?
2.88 x 104

8. You Try How many seconds are in a 40 hour work week? Known
1 hour= ? Minutes
1 minute = ? seconds
Unknown
seconds per a 40 hour work week

9. Practice Problem
The directions for an experiment ask each student to measure 1.84g of copper (Cu) wire. The only copper wire available is a spool with a mass of 50 grams. How many students can do the experiment?
Known
Mass of Cu Available = 50 g
Each student needs= 1.84g/student
Unknown
Number of students?
27 students

10. You Try
An experiment requires that each student use an 8.5 cm length of magnesium (Mg) ribbon. How many students can do the experiment if there is a 570 cm length of magnesium ribbon available?
Known
Length of Mg Available = 570 cm
Each student needs= 8.5 cm/student
Unknown
Number of students?
A 1 degree increase on the Celsius scale is equilavent to a 1.8 degree increase on the Fahrenheit scale. If the temperature increases by 48° C, what is the temperature increase on the Fahrenheit scale?
Known
1°C = 1.8° F
Increase = 48°C
Unknown
Temperature increase in Fahrenheit?

11. Practice Problems
The mass per a unit volume of a substance is a property called density.
The density of manganese (Mn) is 7.21 g/cm3. What is the density of Mn expressed in kg/m3 ?
Known
Mn Density = 7.21 g/cm3
1000 g = 1 kg
100 cm = 1 m
Unknown
Mn Density in kg/m3
7.21 x 103

12. You Try
Gold (Au) has a density of 19.3 g/cm3. What is the density in kilograms per cubic meter?
Known
Au Density = 19.3 g/cm3
1000 g = 1 kg
1003 cm3 = 1 m3
Unknown
Au Density in kg/m3
There are 7.0 x 106 red blood cells (RBC) in 1.0mm3 of blood how many RBCs are in 1.0 L of Blood?
Density of Blood = 7.0 x 106 RBC/ 1.0mm3
1cm3 = 103 mm3
1 cm3 = 1 mL
1000 mL = 1 L
Unknown
Blood’s Density in RBC/L

13. More Practice  Place your answers in scientific notation
The speed of light travels at 3.00 x 1010 cm/s. What is the speed of light in kilometers per an hour?
If an atom of gold has a mass of x 10-22g. How many atoms of gold are in 5.0g of gold?
Convert the following: 7.86 g/cm2 to milligrams per square millimeter.