1st Quarter Chemistry 2012: Electron Configuration

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:

11)         1s²2s²2p⁶3s²3p⁴  ____________________

12)         1s²2s²2p⁶3s²3p⁶4s²3d¹⁰4p⁶5s¹  ____________________

13)         [Kr] 5s²4d¹⁰5p³  ____________________

14)         [Xe] 6s²4f¹⁴5d⁶  ____________________

15)         [Rn]  7s²5f¹¹  ____________________

Determine which of the following electron configurations are not valid:

16)         1s²2s²2p⁶3s²3p⁶4s²4d¹⁰4p⁵ ____________________

17)         1s²2s²2p⁶3s³3d⁵  ____________________

18)         [Ra] 7s²5f⁸  ____________________

19)         [Kr]  5s²4d¹⁰5p⁵ ____________________

20)         [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)