Unit 2 Notes Covalent Bonding Notes Focus Question

Unit 2 Notes Covalent Bonding Notes

Focus Question: �How do electrons behave in a covalent bond?

How are covalent bonds used in daily life? n Methane gas – CH 4 n Water – H 2 O n Sugar!!! – C 6 H 12 O 6 n Propane – C 3 H 8 n Octane – C 8 H 18

What is a covalent bond? �Covalent Bond: atoms share one or more electrons with each other to form the bond. ◦ Forms between two nonmetals

Practice: Which of these would form covalent bonds? a. CH 4 or Na. Cl b. H 2 O or Mg. O

3 Levels of Covalent Bonding Single bond: when 2 atoms share 2 v. e. 2. Double bond: when 2 atoms share 4 v. e. 3. Triple bond: when 2 atoms share 6 v. e. 1. Bond Key = 2 e= 4 e= 6 e-

One Minute Essay (OME) Which level of covalent bonding is the strongest? Why? The strongest type of covalent bond is a _______ bond because __________.

Writing Covalent Molecules Steps 1. Add up the number of valence electrons. The total is the only thing important. Ex. 1: PCl 3

Writing Covalent Molecules Steps Ex. 1: PCl 3 2. Pick the element to write in v. e. = 26 the middle. Usually Carbon (C) or the 1 st element. Write the other elements around the central element.

Writing Covalent Molecules Steps Ex. 1: PCl 3 3. Complete the octet of the v. e. = 26 atoms bonded to the central atom P Cl EXCEPT H and He – only Cl need TWO v. e. Cl

Writing Covalent Molecules Steps Ex. 1: PCl 3 4. Place any leftover electron v. e. = 26 on the central atom, even if doing so results in more Cl P Cl than an octet. If there are not enough electrons to complete the octet of the central atom, try multiple bonds. Cl

Practice: �Ex. 2: Si. H 4 �Ex. 3: HCl �Ex. 4: CCl. H 3

Practice: Ex. 2: Si. H 4

Practice: Ex. 3: HCl

Practice: Ex. 4: CCl. H 3

Summary How do electrons behave in a covalent bond? �In a covalent bond, electrons are _______ between nonmetals.