Results 1 to 3 of 3

Thread: Please help me understand ions and isotopes

  1. #1 Please help me understand ions and isotopes 
    New Member
    Join Date
    Dec 2017
    This may seem like a dumb question, but can someone tell me what causes neutral atoms to end up with more or less neutrons and electrons than they need to remain neutral? My teacher isn't helping me understand how this happens and I already feel stupid.

    I know the definitions. Ions are atoms with a different number of electrons and isotopes are atoms with a different number of neutrons. What I don't know is what happens to those atoms that make them lose or gain neutrons and electrons. Does it happen naturally or some other way? Thanks.

    Reply With Quote  


  3. #2  
    Moderator Moderator Janus's Avatar
    Join Date
    Jun 2007
    Atom can pick up or lose an electron from its environment. The loss can come about by something actually knocking or pulling an electron away from the atom. Positive ions can form when the outer shell of the atom is 1 short of an electron from being full. (electrons arrange themselves in shells around the atom,, these shells are more stable when full, and in some cases, the need to fill the shell over-rides the tendency to be neutral.

    Neutrons are neutral particles themselves, so adding or losing one won't change the neutrality of the atom. They act as part of the "glue" that holds the nucleus together. (a nucleus made of just protons would just fly apart.) It takes a certain minimum number of neutrons in the nucleus to hold any given number of protons together, and in many cases, on or two more won't make any difference, so if the atom is made with an extra one, it remains stable. On the other hand, neutrons by themselves are not stable and tend to decay into a proton and electron. Being in a nucleus with protons stabilizes them. If you try to add too many neutrons to a nucleus, it loses some of that stability and you get a radioactive isotope. Eventually the excess neutron(s) can decay, adding a proton to the nucleus and ejecting an electron (called beta decay), this turns the atom into a different element. which, itself, may be unstable. If it is unstable, it will undergo a further decay. (for example, it may now have too many protons. In which case it will emit a neutron-proton pair by alpha decay) This continues, through a series of alpha and beta decays until a stable nucleus is arrived at.

    This path from radioactive to stable nucleus is called a "decay series". Radioactive isotopes of two different elements can have decay series that take them through the same elements, but different isotopes of those element. And sometime they can lead to the same stable element at the end, but just different stable isotopes of that element. For example, Uranium 235 and Thorium 232 both have decay series that end with a stable lead isotope, but U-235 ends with Lead 207 and Th-232 ends with Lead 209.

    "Men are apt to mistake the strength of their feelings for the strength of their argument.
    The heated mind resents the chill touch & relentless scrutiny of logic"-W.E. Gladstone

    Edit/Delete Message
    Reply With Quote  

  4. #3  
    New Member
    Join Date
    Dec 2017
    Thanks, Janus.
    Reply With Quote  

Similar Threads

  1. Replies: 0
    Last Post: January 15th, 2014, 06:29 PM
  2. Deposition of radioactive isotopes on solids
    By 9gamarus in forum Physics
    Replies: 4
    Last Post: February 24th, 2012, 05:17 PM
  3. Cyclotron cost and use for medical isotopes?
    By icewendigo in forum Physics
    Replies: 3
    Last Post: March 26th, 2011, 01:42 PM
  4. Radio Active Isotopes In My Day
    By William McCormick in forum Pseudoscience
    Replies: 22
    Last Post: May 23rd, 2008, 08:00 AM
  5. Isotopes
    By Raymond K in forum Chemistry
    Replies: 9
    Last Post: March 31st, 2008, 12:06 PM
Posting Permissions
  • You may not post new threads
  • You may not post replies
  • You may not post attachments
  • You may not edit your posts