Lesson 24 Electron Configurations Chem Catalyst These drawings

Lesson 24: Electron Configurations Chem. Catalyst: These drawings show two different ways to represent the arrangement of the electrons in atoms of the element calcium, Ca. 1. Name at least two differences in the drawings. 2. Name at least two similarities in the drawings.

Key Question What does the periodic table indicate about the arrangements of electrons?

Objectives: • • • describe electron shells and subshells in an atom write electron configurations explain how the periodic table shows subshells

Lesson 24 Notes: a. ) Electron shells (levels) are divided into subshells • Main levels are numbered (n = 1, 2, 3…) • The # of subshells = # of the level

b. ) The subshells are called s, p, d, and f • s = 2 max electrons • p = 6 max electrons • d = 10 max electrons • f = 14 max electrons c. ) each subshell gets a number AND letter

d. ) electron configuration: a shorthand way to show electrons are arranged in atoms • The # of electrons in each subshell is written as a superscript

e. ) first 10 elements: • If you add up the superscripts, you should get the atomic number

f. ) The periodic table is organized in subshell blocks.

g. READ) To write out electron configurations, just “” from left to right, row after row • Arsenic = 1 s 22 p 63 s 23 p 64 s 23 d 104 p 3

Check-in 24 1. Identify the element with this electron configuration: 1 s 22 p 63 s 23 p 64 s 23 d 104 p 6 2. What is the electron configuration for tin (Sn)?