Monday, September 03, 2007

Silly Chemistry Question


I thought this question was just plain silly. It's from the "challenge problems" in the Chapter 2 section. So, here goes:


111. Use the concepts in this chapter to obtain an estimate for the number of atoms in the universe. Make the following assumptions: (a) Assume that all of the atoms in the universe are hydrogen atoms in stars. (This is not a ridiculous assumption because over three-fourths of the atoms in the universe are in fact hydrogen. Gas and dust between the stars represent only about 15% of the visible matter of our galaxy, and planets compose a far tinier fraction.) (b) Assume that the sun is a typical star composed of pure hydrogen with a density of 1.4 g/cm^3 and a radius of 7 x 10^8 m. (c) Assume that each of the roughly 100 billion stars in the Milky Way galaxy contains the same number of atoms as our sun. (d) Assume that each of the 10 billion galaxies in the visible universe contains the same number of atoms as our Milky Way galaxy.



SO the reason why I find this amusing is the fact that we have to do a lot of assuming. Lots of which are incorrect. So, was I really finding the estimated amount of atoms in our universe, or in a pretend perfect universe where all the numbers work out just right?

AND...if there really are researchers and such really trying to find out the real answer to this question for our universe, I'm sorry for them. I don't see how knowing the amount of atoms that make up the universe help us at the present moment.

ALSO...I'll give you the answer to the above problem on... whenever I'm on next to blog. I'll put it in a comment under this post.

6 comments:

Rick Edge said...

Is this a Chemistry problem or a geometry problem?
Are you only posting it because you want somebody else to answer it?
I can't wait for the answer!
!!!!!!!!! <-- (pins and needles)

Nedge said...

Ha ha ha! I keep getting different answers, but they are close to what the back of the book gives you:

10^78 atoms/universe

Nedge said...

Which is also: (trying to count in head) 10,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000,000 atoms in the universe...

Melissa said...

My head hurts.

Joslynn said...

So this is what you girls do in chemistry...
Now I know why I'm not part of the club.

Unknown said...

my lect was giving me this question.. n im just like.. ok im dead...