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),
Hereâs where to start: 1  If your employer matches 401k funds, contribute enough to get the full match. 2  Next, if you can contribute to a Roth IRA, work on contributing the full $5,000 a year to that account before you contribute elsewhere.f you have plenty for a rainy day, then you return to your retirement options. If you qualify for a Roth IRA, then thatâs probably where the $5,000 should go. If you donât qualify or have more than $5,000 left to spend, return to your 401k and up your contributions.