1. Scientific Notation

2. Advantages of scientific notation
Allows for very large and very small numbers to be written in a more manageable form
It can make calculations with very large and very small numbers easier if a calculator is not available

3. The general format of scientific notation is
N x 10y
Where 1< N < 10
And y indicates the number of places and direction the decimal moves

4. Positive exponents
To convert into scientific notation we move the decimal behind the first number. Count the number of places moved and that number becomes the exponent on the 10. .
And you get
x 106

5. To put the number back into regular notation you move the decimal back to the right the number of places stated by the exponents
The exponent is 4, therefore the decimal moves 4 places.
3 678
3 678 x 104 .
And you get 36780

6. Negative Exponents
To convert into scientific notation, we move the decimal behind the first non-zero digit.
The number of spaces moved becomes the exponent on the 10, but as a negative. .
1.23 x 10-3

7. Scientific Notation 65,000 kg  6.5 × 104 kg
Converting into Sci. Notation:
Move decimal until there’s 1 digit to its left. Places moved = exponent.
Large # (>1)  positive exponent Small # (<1)  negative exponent
Only include sig figs.

8. Scientific Notation Type on your calculator: = 671.6049383 = 670 g/mol
Calculating with Sci. Notation
(5.44 × 107 g) ÷ (8.1 × 104 mol) =
Type on your calculator:
EXP EE
EXP EE
ENTER
EXE
5.44 7
8.1 ÷ 4 =
= 670 g/mol
= 6.7 × 102 g/mol

9. Using a Calculator Type in the number
Press Exp and enter the exponent value
DO NOT MULTIPLY BY 10. The exp does that for you.

10. Type in the number
Press Exp and enter the exponent value
DO NOT MULTIPLY BY 10. The exp does that for you.

11. Type in the number
Press EE and enter the exponent value
DO NOT MULTIPLY BY 10. The EE does that for you.

12. Type in the number
Press 2nd x-1 and enter the exponent value
DO NOT MULTIPLY BY 10. The 2nd x-1 does that for you.

13. Type in the number
Press Exp and enter the exponent value
DO NOT MULTIPLY BY 10. The exp does that for you.

14. Copying Answers from a calculator
If answer on calculator looks like this X X 27
2E7
Do not write it like that!!!
Instead, write it as 2 x 107

15. Practice Problems (7.35X10-11)(3.21X1023)(1.69X10-19)
( )(757391)(250
(7531)(2.53X1021)
(3.576X10-5)(6.35X107)(523)
(32571)(7.55X1057)
= 2.3X10-27
=3.5X10-21