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This lesson covers the formation of covalent bonds through shared electrons among atoms. You will draw electron dot structures for Chlorine, Oxygen, Carbon, and Nitrogen, determining their valence electrons. It explains how atoms form bonds to achieve a full valence shell like noble gases, emphasizing the importance of covalent bonding in organic molecules like proteins and cell membranes. Through examples, you will learn how many bonds atoms can form based on their unpaired electrons. Complete the assigned homework and worksheet to reinforce your knowledge.
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Catalyst (5 minutes) Draw electron dot structures for the following elements (find the number of valence electrons!) ON A SEPARATE SHEET OF PAPER (KEEP IT FOR THE WEEK): 1. Chlorine 3. Oxygen O Cl 2. Carbon 4. Nitrogen C N
What we’ve learned so far…. • Atoms lose/gain electrons to form cations and anions (8 valence electrons like a noble gas!) • Charged anions and cations form IONIC BONDS to make IONIC COMPOUNDS - K F +
What we’re learning today… • Atoms can also SHARE electrons to form COVALENT BONDS! • Why is this important? • Covalent bonds are important in many organic molecules (living creatures) • Examples: • Cell membranes are made of lipids (We’d be puddles of liquid without them!) • Proteins (We’d starve without them!)
Covalent Bond • The chemical bond formed when two atoms SHARE electrons • Why do atoms form bonds? To gain the same number of valence electrons as a noble gas! Cl Cl Full octet (8)! Full octet (8)! Bonding Pair
Types of Covalent Bonds • Single Bond: ONE pair of shared electrons • Double Bond (Pi Bond): TWO pairs of shared electrons • Triple Bond: THREE pairs of shared electrons Cl Cl O O N N
How many bonds can an atom form? • # bonds formed = # of UNPAIRED electrons • # electrons atoms keep = # electrons in PAIRS 3 unpaired electrons N N = 3 bonds! O 2 pairs = four electrons the atom keeps!
Example 1 • How many bonds can Sulfur form? • How many electrons will Sulfur keep to itself? Two unpaired electrons! S Two bonds can be formed! Two pairs of electrons! S Four electrons will be kept by sulfur!
Example 2 • How many bonds can Carbon form? • How many electrons will Carbon keep to itself? Four unpaired electrons! C Four bonds can be formed! No pairs of electrons! C Zero electrons will be kept by carbon!
Example 3 • How many bonds can Neon form? • How many electrons will Neon keep to itself? Zero unpaired electrons! Ne Zero bonds can be formed! Four pairs of electrons! Ne Eight electrons will be kept by neon!
Announcements • Homework – Due Fri Feb 4 • Read Sec 8.1, pp 240-247 • Define vocab on p 240 (7 words) • Choose any 3 of the words and draw an illustration to show what they mean
Worksheet • COMPLETE the worksheet