The median Social Security benefit was $16,295 for men and $11,999 for women in 2012, AARP found. Retirement savings. Just under a third (30 percent) of retirees receive income from either a traditional pension or take withdrawals from a retirement savings account such as a 401(k) or individual retirement account.
The Sodium atom. 1  The Na atom has an equal number of electrons and protons (11 e-and 11 p+). 2  This atom too is unstable because the outer valance shell of electrons has only one electron in it. 3  To be stable the outer shell of electrons should have eight electrons.
Introduction: The effective nuclear charge is the pull that the specific electron feels from the nucleus. Example; hydrogen atom contains one proton and one electron. The effective nuclear charge on electron is equal 1 in hydrogen atom. Helium contains two protons and two electrons. But there is not the effective nuclear charge equal 2 on each electron in helium atom, it is about 1.7 units. There is some rules for calculation the effective nuclear charge in modern physics. But there are not analyses about it.