1. Not finding help here? Sign up for a free 30min tutor trial with Chegg Tutors
    Dismiss Notice
Dismiss Notice
Join Physics Forums Today!
The friendliest, high quality science and math community on the planet! Everyone who loves science is here!

Help on Chem problem!

  1. Mar 29, 2005 #1
    This is the equation I am supposed to write and balance:
    The formation of solid iron (III) chloride
    from its elements.

    I tried to write it like this- 3Fe + 2Cl = 2FeCl3
    But my teacher then asked: How does chlorine exist as an element?What I mean is if I have a container full of chlorine at room temperature the chlorine exists as Cl2 molecules . Other nonmetals also exist like this such as O2 and N2.
    I'm not sure what this means and how to solve the equation. Can someone help please?
  2. jcsd
  3. Mar 29, 2005 #2


    User Avatar
    Science Advisor

    It means the equation should be written and balanced using the Cl2 molecule like it exists under standard conditions, that is, with Cl2:
    2Fe + 3Cl2 ⇒ 2FeCl3

    Similarly, the formation of water would be written:
    2H2 + O2 ⇒ 2H2O

    Last edited: Mar 29, 2005
  4. Mar 29, 2005 #3


    User Avatar
    Science Advisor
    Homework Helper

    Incidentally,pay attention to wording:chlorine exists as an element,but under normal pressure & temp.conditions it is only made up of diatomic molecules...

  5. Apr 3, 2005 #4
    The same can be said of hydrogen and most of the other elements in groups 6 and 7 because of those elements' tendency to bond with something to gain a total of eight electrons in their outer electron shell.
  6. Apr 4, 2005 #5


    User Avatar
    Science Advisor
    Homework Helper

    Halogens,nitrogen,oxygen & hydrogen form diatomic molecules.Sulphur & phosphorus are a bit weird.

Know someone interested in this topic? Share this thread via Reddit, Google+, Twitter, or Facebook

Have something to add?

Similar Discussions: Help on Chem problem!
  1. Chem problem (Replies: 1)

  2. General Chem Help (Replies: 3)

  3. Chem/Math Help (Replies: 5)