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Periodic trends

  1. Nov 9, 2015 #1
    Hey guys we say that when in periodic table we go from left to right atomic size decreases because of increase in nuclear charge in the same shell but my question is that the electron to proton ratio is 1:1 then how nuclear charge is increased. Some say nuclear charge is concentrated but my attention is still there on 1:1 ratio of proton to electron. Can u explain this ?
  2. jcsd
  3. Nov 10, 2015 #2
    You seem to have the idea that each proton and electron cancel out the other's electric field. Really, the nucleus acts as a large positive particle that pulls each electron individually. Increasing the charge of the nucleus increases the pull, thereby decreasing the atomic radius.
  4. Nov 10, 2015 #3
    You wanna say that i shouldn't see to that ratio of 1:1 but to consider as nuclear charge increases in a particular shell so it attracts electrons more strongly. Like this?
  5. Nov 10, 2015 #4
    Yes. Look into Coulomb's Law if you would like to understand why.
  6. Nov 10, 2015 #5
    Ohk ty
  7. Nov 10, 2015 #6
    Hey i went for Coulomb's law its force on charged particles are expressed mathematically as F=k Q q/ r^2 that means as distance between outer shell and nucleus is constant but both electron charge and proton charges are increasing so the force of attraction will be increased
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