Quiz

1
Quiz

• Please write the following in exponential
  notation
• 1500 m the equivalent of a mile
• 0.000000750 m the wavelength of red light
• Please write the following as a ordinal number
• 3.00 x 108 m/s The speed of light

2

Messing Around With Big Numbers

• Exponents
• They really do make life easier
• 300000000 m/s Speed of light in a vacuum
• 3.00 x108 m/s
• 602200000000000000000000 molecules/mole
• 6.022 x1023 molecules/mole

3

Messing Around With Big Numbers

• Two Parts
• Coefficient
• Exponent
• 3.00 x108 m/s
• Coefficient
• 6.022 x1023 molecules/mole

Exponent
4

Messing Around With Big Numbers

• 3.00 x108 m/s
• 6.022 x1023 molecules/mole

Multiply or divide
Add or subtract
How far does light travel in a minute (3.00 x108
)m/s x (6.0x101s) 18x109 m 1.8x1010
5
SI prefixes that help us out

• King Henry Died Drinking Chocolate Milk
• Kilo Hecta Deca Base Deci Centi Milli
• 103 102 101 10-1 10-2
  10-3
• Handy units that will come up in the course
• Micro µ 10-6 nano 10-9 Pico 10-12
• Giga 109 Mega 106

6
Chapter One
The Air We Breathe
7
Chem 108 Environmental Chemistry

• The math
• Determining the Radius Diameter/2
• Determining an Average Radius
• (Total of all measurements)/(The number of
  measurements)
• Determining the Volume of a Sphere
  V4/3pr34/3x3.14x(5.82cm)3 827cm3
• Vvolume rradius and p3.14 since we started in
  cm we end with cm3.
• Because 1 mL/1 cm3 then 827cm3x (1 mL/1 cm3)
  827mL

8
Chem 108 Environmental Chemistry

• More math
• ml is 1/1000 of a liter to get l multiply by the
  conversion factor(the same as dividing by 1000).
  827 mL 0.827L
• there is 1 mole / 24.5 L of gas at room
  temperature and standard pressure so to convert
  to moles multiply by the conversion factor
  (again this is the same as dividing by
  24.5) 0.827L x (1 mole/24.5L) 0.0337 mole
• There is 6.02 x 1023 molecules/mole multiply by
  the conversion factor to determine molecules.
  0.0337 mole x(6.02 x 1023 molecules/mole)
  2.03 x 1022 molecules

9
The Composition of Our Air
Its a mixture a physical combination of two or
more substances present in variable amounts
1.2