Week 5
CLASS 1: Electron configuration
We already know that atoms are made of
protons, neutrons, and electrons—but where
exactly are those electrons? 🤔 Electrons
don’t just move around the atom randomly;
they are arranged in specific energy levels
around the nucleus called ORBITALS. This
is called electron configuration.
In this lesson, you’ll learn how to figure out where an atom’s electrons are located and how to write its electron configuration using a simple set of rules. By the end, you’ll be able to look at an element on the Periodic Table and use its atomic number to work out how its electrons are arranged!
Let's start by paying attention to the introductory presentation while you take notes on your notebook:
Then, solve the following activity in your notebook:
1. Write the electron configuration of the following elements:
• Iron
• Potassium
• Bromine
• Chlorine
• Manganese
2. Repeat this process for the elements of the first group of the periodic table: Li, Na, K, Cs. What do you see in common in their electron configuration? (check the last part of the configuration)
We know that atoms are constantly interacting
with the world around them, but have you ever
wondered why some atoms bond with others?
The answer has a lot to do with their electrons!
Atoms tend to become more stable when their
outer energy level is full, so they like to form
bonds that help them achieve this!
Atoms don’t bond randomly. There is a pattern behind the way they gain, lose, or share electrons. Today we will learn how atoms gain, lose, or share electrons to become more stable and how this helps explain the formation of bonds.
Then, solve the Classwork in your NB:
Use the table of the valence electrons to answer these questions:
1) Why aren’t noble gases reactive elements? (they are group 18 of the periodic table, last column)
2) Write the electron configuration for these elements and use it to know how many valence electrons they have:
Sulfur Iodine
3) Explain with your own words the rule that elements follow to make compounds.
4) Explain how the following molecules satisfy the octet rule (find the valence electrons of each element using the table above) and show the math they have to fulfill the octect rule:
H2O NaCl
CH4 LiF
5) How do metals change to obey
the octet rule? (lose/gain)
6) How do non-metals change to
obey the octect rule? (lose/gain)
7) Use the table that shows the valence electrons for these elements and decide how can they combine to make compounds and obey the octet rule: Combine them to form at least 4 possible compounds:
Na Al K O N Ca Br F
CLASS 2: The Octet Rule, why do atoms bond?
