1. Limited time only! Sign up for a free 30min personal 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!

Homework Help: Atomic radii for irridium

  1. Jun 15, 2006 #1
    hey just wondering where I went wrong

    Iridium Crystallizes in a face centred cubic unit call that has an edge length of 3.833A
    The atom in the cantre of the face is in contact with the corner atoms

    calculate the atomic radii of the irridium atom
    I did this
    using pythag, (3.833^2)+(3.833^2)=c^2
    b^2= 29.384
    Then I divided it by 2 as it was the radius and got 2.710
    But I am assuming that this is wrong due to the qu asking for the atomic radii. So I divide it by 192.272 and I still get the wrong answer.
    The answer is meant to be 1.355Angstrom

    So if anyone could tell me where I went wrong I would be much appreciative
  2. jcsd
  3. Jun 15, 2006 #2


    User Avatar
    Gold Member

    Hello Taryn,

    try to revisualise one face. How many atom-radii will fit into the length of the face-diagonal? You are close to the correct answer. :smile:


    Last edited: Jun 15, 2006
  4. Jun 15, 2006 #3
    figured it out, u divide by 2 as the atomic radii is being asked for and there are two atoms. So simple!
Share this great discussion with others via Reddit, Google+, Twitter, or Facebook

Similar Threads for Atomic radii irridium Date
If atoms are neutral, how do they share electrons Jan 30, 2018
Radii of Mg2+ and O2- in MgO Apr 11, 2016
Atomic and ionic radii Mar 29, 2014
How are atomic radii and H-bond strength related? Jan 20, 2009
Atomic radii question May 31, 2008