scientific notation

Scientific Notation - A way to express numbers so you don't have to write a lot of numbers.

Write the following number down and then follow the dots...

602,000,000,000,000,000,000,000.

.

...you didn't actually write it down did you? Probably because that's a crazy amount of 0's to write! Welp, scientists don't want pages and pages with crazy big numbers so they express that number like this:

6.02X10²³

^{instead of:}

602,000,000,000,000,000,000,000.

^{Much better right? Yeah, that's kind of the whole point of this.}

^{6.02 X 1023}

^{If you did write it down congrats! That number is really important in chemistry called a "mole"}

^{The good news is, you won't ever have to write that number out again!}

^{Consolation picture for you.}

^{Read and/or watch the khan academy video to find out how!}

Scientific Notation is pretty easy... you just gotta know

Three Rules:

(1) Change your number to be a single whole number and add X10 after it:

10 becomes 1.0 X10

Add an exponent:

(2) Exponent is how many places you moved the decimal.

10 = 1.0 X 10¹

123432134. becomes 1.2343214 X 10⁷

^{(moved the decimal 7 places to the left)}

(3)Exponent is negative if you moved the decimal to the left to do this.
(another way to look at it: if you made the number bigger, the exponent is negative).

.00001 becomes 1.0 X 10^-5

^{(moved the decimal 7 places to the right)}

You can check your answers by punching your numbers in the calculator. They should come out to be the same number!

Calculator Exponent Keys:

EXP

EE

^

Still confused? Check out this video (Khan Academy):

OH SWEET IT'S THE Scientific Notation Song!

:-)

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