Review: Electron Configurations

s orbital (1) - spherical

p orbitals (3) – dumb-bell shaped

d orbitals (5)

f-orbitals (7)

Review: Electron Configurations Principal energy levels: n = 1 to 7 (row #) Energy sublevels: s,p,d,f Orbitals: describes the electron’s location orbitals are not necessarily spherical maximum of 2 electrons per orbital s = 2 p= 6 d = 10 f = 14 Example: Sodium (Na)-11 electrons 1s22s22p63s1

Noble Gas Configuration

What are Noble Gases? Noble gases are found in group 8A The elements are called noble because they are non-reactive and very stable. They do not tend to form compounds 8A 7A 6A 5A 3A 4A 1A 2A

Complete Electron Configuration What is the electron configuration for Ne? Ne: 1s22s22p6 What is the electron configuration for Mg? Mg: 1s22s22p63s2 What do both electron configurations have in common? [Ne] =1s22s22p6

Noble Gas Configuration (Abbreviated Configuration) Using neon’s configuration and then adding magnesium’s extra electrons we can get the noble gas configuration. Ne: 1s22s22p6 Mg: 1s22s22p63s2 Noble gas configuration Mg: [Ne]3s2 Only use noble gases in the brackets.

Which Noble Gas is Used? To figure out which noble gas to use find the noble gas that is closest to the element without going over in atomic number Which noble gas is closest without going over? Rb Cl Ra [Kr] [Ne] [Rn]

Blocks of the Periodic Table There are s, p, f, and d blocks of the periodic table which correspond to the energy sublevels.

s Block Elements Write the closest noble gas without going over in brackets. Use the row number to get the energy level. Count the number of electrons until you get to the element in the s block. 1 2 3 4 5 6 7 Mg: [Ne] 3 s2 Mg

Question Time Try other s-block elements. Write the noble gas configuration of the following elements Cs Ca [Xe]6s1 [Ar]4s2

p block elements (Between 5-18) Write the closest noble gas without going over in brackets. Use the row number to get the energy level. Write s2 after the row number because you have to go through the s-block to get to the p-block. Write the row number again The write “p” and then count the number of p electrons you must get through to get to your element as a superscript 1 2 3 4 5 6 7 Si: [Ne] 3 s2 3 p2 Si

Question Time Try other p-block elements. Write the noble gas configuration of the following elements N S [He]2s22p3 [Ne]3s23p4 1 2 3 4 5 6 7

d block elements (Between 21-48) Write the closest noble gas without going over in brackets. Use the row number to get the energy level. Write s2 after the row number because you have to go through the s-block to get to the d-block. Write one less than the row number (d-block elements are always one less than the row number)**d for down one row number Then write “d” and count the number of d electrons you must get through to get to your element as a superscript 1 2 3 4 5 6 7 3d 4d 5d 6d Co: [Ar] 4 s2 3 d7 Co

Question Time Try other d-block elements. Write the noble gas configuration of the following elements Ti Zn [Ar]4s23d2 [Ar]4s23d10 1 2 3 4 5 6 7 3d 4d 5d 6d

p block elements (Between 31-53) Write the closest noble gas without going over in brackets. Use the row number to get the energy level. Write s2 after the row number because you have to go through the s-block to get to the p-block. Write one less than the row number (d-block elements are always one less than the row number)**d for down one row number Then write “d” and count the number of d electrons you must get through to get to your element as a superscript Write the row number again and “p” and count over the number of p electrons until you get to your element 1 2 3 4 5 6 7 3d 4d 5d 6d Br: [Ar] 4 s2 3 d10 4p5 Br

Question Time Try other p-block elements. Write the noble gas configuration of the following elements Sn Se [Kr]5s24d105p2 [Ar]4s23d104p4 1 2 3 4 5 6 7