Electron Configuration Practice Worksheet

In the space below, write the unabbreviated electron configurations of the following elements:

1)sodium ________________________________________________

2) iron ________________________________________________

3) bromine ________________________________________________

4) barium ________________________________________________

5) neptunium ________________________________________________

In the space below, write the abbreviated electron configurations of the following elements:

6) cobalt ________________________________________________

7) silver ________________________________________________

8) tellurium ________________________________________________

9) radium ________________________________________________

10) lawrencium ________________________________________________

Determine what elements are denoted by the following electron configurations:

1s22s22p63s23p4 ____________________

1s22s22p63s23p64s23d104p65s1 ____________________

[Kr] 5s24d105p3 ____________________

[Xe] 6s24f145d6 ____________________

[Rn] 7s25f11 ____________________

Determine which of the following electron configurations are not valid:

1s22s22p63s23p64s24d104p5 ____________________

1s22s22p63s33d5 ____________________

[Ra] 7s25f8 ____________________

[Kr] 5s24d105p5 ____________________

[Xe] ____________________

Electron Configurations - Solutions

 

Note:  The electron configurations in this worksheet assume that lanthanum (La) is the first element in the 4f block and that actinium (Ac) is the first element in the 5f block.  If your periodic table doesn’t agree with this, your answers for elements near the f-orbitals may be slightly different.

 

1)            sodium            1s22s22p63s1

 

2)         iron                  1s22s22p63s23p64s23d6

 

3)            bromine             1s22s22p63s23p64s23d104p5

 

4)         barium             1s22s22p63s23p64s23d104p65s24d105p66s2

 

5)            neptunium             1s22s22p63s23p64s23d104p65s24d105p66s24f145d106p67s25f5

 

6)         cobalt              [Ar]  4s23d7

 

7)         silver               [Kr]  5s24d9

 

8)            tellurium         [Kr]  5s24d105p4

 

9)         radium            [Rn]  7s2

 

10)            lawrencium    [Rn]  7s25f146d1

 

11)             1s22s22p63s23p4  sulfur

 

12)             1s22s22p63s23p64s23d104p65s1  rubidium

 

13)             [Kr] 5s24d105p3  antimony

 

14)             [Xe] 6s24f145d6  osmium

 

15)             [Rn]  7s25f11  einsteinium

 

16)             1s22s22p63s23p64s24d104p5 not valid (take a look at “4d”)

 

17)             1s22s22p63s33d5  not valid (3p comes after 3s)

 

18)             [Ra] 7s25f8  not valid (radium isn’t a noble gas)

 

19)             [Kr]  5s24d105p5 valid

 

20)      [Xe]  not valid (an element can’t be its own electron configuration)