1. Dividing with Scientific Notation How can we deal with so many zeros? The mass of one carbon atom = 12.01 602,200,000,000,000,000,000,000

2. Covered in this lesson This lesson demonstrates how to divide with scientific notation. – Scientific notation can be divided easily with or without a calculator when the factors (the number between 1 and 10) and exponents (power of ten) are considered.

3. Scientific Notation All scientific notation is expressed with a factor multiplied by a power of 10. Examples A.5.89 X 10 7 mB. 3.0 X 10 18 dL C. 9.00 X 10 -3 gD. 7.1 X 10 -12 Mm

4. Methods of Dividing There are at least two methods you can use to divide in scientific notation. – The short hand way using a scientific calculator. – The long hand way without a scientific calculator.

5. Using a Scientific Calculator If you are dividing in scientific notation use the following method. – Enter the first number in ( ) divided by the second number in ( ) – Press enter (Note the power of 10 will be given the symbol exp)

6. Example: Scientific Calculator (1.47 X 10 7 ) / (6.00 X 10 10 ) = Put the first number in ( ) divide by the second number in ( ) It looks like this (1.47*10^ 7 )/(6.00*10^ 10 ) Press enter you see 2.45exp-4 Write your answer 2.45 X 10 -4

7. 2 nd Method Using a Scientific Calculator Use the exp key dividing as usual. Enter the numbers as follows: – first number: factor, exp key, exponent – divide – second number: factor, exp key, exponent – Enter

8. Example: 2 nd Method Scientific Calculator (1.47 X 10 7 ) / (6.00 X 10 10 ) = Use the exp key and just divide. It looks like this 1.47exp7/6.00exp10 Press enter you see 2.45exp-4 Write your answer 2.45 X 10 -4

9. Example: Without Calculator Divide the factors Subtract the power of 10 exponents Put them together Change back to scientific notation.

10. Without Calculator Example (1.47 X 10 7 ) / (6.00 X 10 10 ) = Divide the factors 1.47/6.00 = 0.245 Subtract the exponents 7 - 10 = -3 Put them together 0.245 X 10 -3 change back to scientific notation. = 2.45 X 10 -4 the final answer

11. Practice problems 1.(6.38 X 10 9 ) / (7.83 X 10 5 ) = 2.(2.038 X 10 7 ) / (2.00 X 10 -11 ) = 3.(5.89 X 10 -5 ) / (3.0 X 10 10 ) = 4.(9.00 X 10 -8 ) / (7.1 X 10 -4 ) =

12. Answers Practice Problems 1.8.15 X 10 3 2.102 X 10 6 3.1.96 X 10 -15 4.1.27 X 10 -4