The third-period elements can hold up up to 18 valence shell electrons. Apparently third-period elements can depart from the octet rule by having more than eight electrons in their valence shells. From the choices you have given, P, Cl, Se and Sn are all capable of having more than 4 pairs of valence electrons.his automatically eliminates carbon, oxygen, boron and fluorine. Tin will tend to form either a +2 or +4 ion, so that's eliminated. Chlorine is in the 3rd period, but because of it's high electronegativity, it will never be the central atom in a compound.
Amount of your reduced Roth IRA contribution. If the amount you can contribute must be reduced, figure your reduced contribution limit as follows. 1  Start with your modified AGI. 2  Subtract from the amount in (1): 3  $183,000 if filing a joint return or qualifying widow(er),f the amount you can contribute must be reduced, figure your reduced contribution limit as follows. 1  Start with your modified AGI. 2  Subtract from the amount in (1): 3  $183,000 if filing a joint return or qualifying widow(er),
the five year period for qualified withdrawals starts on january 1 of the first tax year for which you make a roth contribution example 1 you established your first roth ira with a regular annual contribution on april 15 2009the contribution was for the 2008 tax yearhe five year period for qualified withdrawals starts on january 1 of the first tax year for which you make a roth contribution example 1 you established your first roth ira with a regular annual contribution on april 15 2009 the contribution was for the 2008 tax year