Write the probability of four quantum numbers of the last electron for the following elements:

                                         ₅B                   ,                   ₉F                    ,                 ₁₁Na

Sol:

₅B : 1s²,2s² ,2p¹

n= 2    ,    l= 1   ,    ml =-1    ,  ms= 1/2

₉F: 1s²,2s² ,2p⁵

n= 2    ,    l= 1   ,    ml =0    ,  ms=-1/2

₁₁Na : 1s²,2s² ,2p⁶  , 3s¹

n= 3    ,    l= 0   ,    ml =0    ,  ms= 1/2