Lesson 4: Aim and Objectives
Aim: How do we use models and diagrams to
depict molecules?
Objectives:
1. Learn to draw structural diagrams of
molecules.
2. Learn to draw Lewis Dot Structures for
covalent compounds.
Modeling Molecules
Ball-and-Stick Molecular Models
1. What shape structure would be the best to
represent an atom?
2. How can we depict bonds between atoms?
3. How can the model show the number of
bonds each atom can make?
4. How can you depict a double bond between
two atoms?
5. Given the elements H, C, O, S, N, P, Cl, Br;
which balls in the model kit could be used to
represent them?
Molecule Shapes
Match the following
names to the structure:
-linear
-bent
-tetrahedral
-pyramidal
Molecular Model Activity
1. Get in your element groups.
2. Use the model kit to make the molecules on
the lab sheet.
3. Complete the chart. You will be given
additional time to complete this in lab.
Regents Question Warm-Up
1.
When lithium reacts with bromine to form the compound LiBr, each lithium atom
(1) gains one electron and becomes a negatively charged ion
(2) gains three electrons and becomes a negatively charged ion
(3) loses one electron and becomes a positively charged ion
(4) loses three electrons and becomes a positively charged ion
2.
Given the balanced equation representing a reaction:
N2 + energy → N + N
Which statement describes this reaction?
(1) Bonds are broken, and the reaction is endothermic.
(2) Bonds are broken, and the reaction is exothermic.
(3) Bonds are formed, and the reaction is endothermic.
(4) Bonds are formed, and the reaction is exothermic.
3.
Which formulas represent one ionic compound and one molecular compound?
(1) N2 and SO2 (2) BaCl2 and N2O4
(3) Cl2 and H2S (4) NaOH and BaSO4
Regents Question Warm-Up
1. A sample of a substance has these characteristics:
–
–
–
–
melting point of 984 K
hard, brittle solid at room temperature
poor conductor of heat and electricity as a solid
good conductor of electricity as a liquid or in an aqueous solution
This sample is classified as
(1) a metallic element
(2) a molecular compound
(3) a radioactive element
(4) an ionic compound
2. Given the formula for hydrazine:
How many pairs of electrons are shared
between the two nitrogen atoms?
(1) 1
(2) 2
(3) 3
(4) 4
3.
Which of the following types of substances would have covalent
bonds? There may be more than one correct answer.
a) molecular solid
c) ionic solid
b) metallic solid
d) network solid
Homework 4
Workbook:
Pg. 99-111
1-44 Booyah!
(Don’t wanna hear it…you have three days to do it!)