1. Scientific Notation

2. In science, we deal with some very LARGE numbers: 1 mole = 602000000000000000000000 In science, we deal with some very SMALL numbers: Mass of an electron = 0.000000000000000000000000000000091 kg Scientific Notation

3. Imagine the difficulty of calculating the mass of 1 mole of electrons! 0.000000000000000000000000000000091 kg x 602000000000000000000000 x 602000000000000000000000 ???????????????????????????????????

4. Scientific Notation: Rules A method of easily representing very large or very small numbers in the form: M. x 10 n M. x 10 n  M is a number from 1 to 9  The decimal ALWAYS must be located to the right of the single number.  n is an exponent  For numbers less than 1 the exponent is negative: 10 -n  Your calculator will use E n instead of x 10 n  On a calculator you press EE or 10 X on “less deluxe" models…

5. 2 500 000 000 Step #1: Insert an understood decimal point. Step #2: Decide where the decimal must end up so that one number is to its left up so that one number is to its left Step #3: Count how many places you bounce the decimal point the decimal point 1234567 8 9 Step #4: Re-write in the form M x 10 n Rules for numbers greater than 1:

6. 2.5 x 10 9 The exponent is the number of places we moved the decimal. Rules for numbers greater than 1:

7. How to reverse? 1.For numbers with a positive exponent (greater than one): 2.Move the decimal place right by the exponent 3.This makes it bigger. 6.23 x 10 9 REVERSE for numbers greater than 1:

8. 0.0000579 Step #2: Decide where the decimal must end up so that one number is to its left up so that one number is to its left Step #3: Count how many places you bounce the decimal point the decimal point Step #4: Re-write in the form M x 10 n 12345 Step #1: Insert an understood decimal point Rules for numbers LESS than 1:

9. 5.79 x 10 -5 The exponent is negative because the number we started with was less than 1. Negative exponents mean 1 over the number without an exponent: 5.79 x 10 5 1

10. 1.78 x 10 -9 REVERSE for numbers LESS than 1: How to reverse? 1.For numbers with a negative exponent (less than one): 2.Move the decimal place LEFT by the exponent 3.This makes it smaller.