# Chemical Forums

## Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: Username on April 19, 2004, 10:17:19 AM

Title: Order of magnitude
Post by: Username on April 19, 2004, 10:17:19 AM
Can you guys explain the expression "order of magnitude" to me?

A book I'm reading says: "The angstrom is a convenient unit because the lighter atoms are on the order of magnitude of 1 A."

I know it has something to do with rough estimations since the book also says that for example a number between 3 and 30 is on the order of magnitude of 10.
Title: Re:Order of magnitude
Post by: Mitch on April 19, 2004, 01:04:37 PM
10 is an order of magnitude above 1. 100 is an order of magnitude above 10.
Title: Re:Order of magnitude
Post by: gregpawin on April 19, 2004, 04:00:27 PM
In other words, if express numbers in scientific notation: 2.22 X 103, the exponential number is the magnitude.  If you're comparing something and its not quite one base number higher, then you call it a factor of X higher... 6 is higher than 3 by a factor of 2, but 60 is higher than 6 by one order of magnitude.
Title: Re:Order of magnitude
Post by: Username on April 20, 2004, 07:36:37 AM
Hehe OK I think I finally got it.
It  usually takes a while for me to understand the simple things...let's me look kinda dumb from time to time  ::)

Edit:
Thanks for the explanations.