April 23, 2024, 07:20:28 PM
Forum Rules: Read This Before Posting


Topic: Basic Problem-Moles-Molecules  (Read 2995 times)

0 Members and 1 Guest are viewing this topic.

Offline adkinsjr

  • Regular Member
  • ***
  • Posts: 18
  • Mole Snacks: +0/-0
Basic Problem-Moles-Molecules
« on: November 18, 2009, 01:47:37 PM »
I need to find the number of water molecules in of

The density of water at 4 degrees C is given as therefore contains at that temperature.



If there is anything wrong with the latex, I will be editing it.

I'm not sure how to relate the number of molecules to the number of moles. I know how to find the number of atoms of any element. So could I just find the number of hydrogen atoms in 1 mole of $$H_2O }[/img] and then divide that number by 2? Or I guess it would just be easier to find the number of oxygen atoms in 1 mole. 1 water molecule contains 1 oxygen atom.

Offline adkinsjr

  • Regular Member
  • ***
  • Posts: 18
  • Mole Snacks: +0/-0
Re: Basic Problem-Moles-Molecules
« Reply #1 on: November 18, 2009, 01:54:30 PM »
Actually, I think it's simplier than I though. The number doesn't seem to apply exclusively to atoms. So I should be able to use the conversion factor  right?


Offline cth

  • Full Member
  • ****
  • Posts: 223
  • Mole Snacks: +36/-8
Re: Basic Problem-Moles-Molecules
« Reply #2 on: November 18, 2009, 03:56:03 PM »
Yes, simply multiply by NA the mole number you have to get the number of molecules.

One mole of something (it could be anything like atoms, molecules, cars, stars,...) is always defined as containing NA objects. Just like a dozen is defined as containing 12 objects.

Sponsored Links