Download Learning Target: Design and Plan a Scientific

10th Grade Chemistry: 1/22/14
Learning Target:
Design and Plan a Scientific Investigation to Compare the Structure of
Substances at the Bulk Scale to Infer the Strength of Electrical Forces
Between Particles….and…
Communicate scientific and technical information about why the molecular
level structure is important in the functioning of designed materials
Agenda:
•Must Do
•WWD
•Brief Lesson
•Lab!!!!
What’s the caption?
Must Do:
 Write a brief statement about your knowledge of
molecular (covalent) vs. ionic compounds
WWD
 Picture Clues….one word, four syllables
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Polarity!
Definition
Noun
(1) The presence of or having distinct and opposite
poles
(2) The condition of having contrasting properties or
direction
(3) (chemistry) The tendency of forming distinctive
opposing charges based on the orientation of
chemical bonds and spatial structure of the
molecule
How to tell the difference between a molecular
and ionic compound
 Use the periodic table!
Compounds and Chemical Formulas
 Molecule - A single particle, contains two
or more nonmetal atoms; covalently
bonded
 Formula Unit – a particle containing a
metal with a nonmetal; ionicly bonded
 Chemical formulas – give the number of
atoms of each element in a compound
Identifying Ionic and Molecular Compounds
Which of the following compounds would you
expect to be ionic: N2O, Na2O, CaCl2, SF4?
Which of the following compounds are molecular:
CBr4, FeS, P4 O6, PbF2 ?
Which combination is likely to
produce an ionic compound?
 C and H
 S and Cl
 Ca and F
 Br and I
 Xe and F
Which combination is likely to
produce an ionic compound?
 C and H
 S and Cl
 Ca and F
 Br and I
 Xe and F
Solubility
 Important concept for the lab
 Do you expect that ionic compounds will dissolve in nonpolar, somewhat polar, or polar liquids?
 Will molecular compounds dissolve in non-polar, somewhat
polar or polar liquids?
 Alcohol in water?
 Acetone in water?
 Sugar in water?
 Sugar in Acetone?
 Mineral oil in water, acetone, alcohol?
 In general “like dissolves like”
Useful Links
 Polarity Index
 Water Solubility Data
 Solubility Table
 Solubility Chart
Lab!
•Build the Best Battery
Make a matrix of materials and
measure the electrical properties of
your cell
Try to get the most voltage out of your
Cell (cells….this is a hint).
The winning group gets to do a victory
dance
Matrix Example
Lab Rules
Lab Rules Continued
 Please dump waste in the orange bucket
 Go easy on the Isopropyl and acetone
 Try not to spill!