Chemistry 102
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Dr. Don DeCoste
367J Noyes Lab
decoste@illinois.edu
3-4 pm Tuesdays and Thursdays
By appointment; open door policy
http://chem.illinois.edu
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To Do
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Continue reading Chapter 3.
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Text homework for Chapter 3.
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Quiz on Friday (1-3.4)
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Lon-Capa assignment #1.
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Using The Periodic Table
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Symbol, name, number of protons (all of
these are related).
Number of electrons in a neutral atom or
in ion.
Charges for common ions.
Metals and non-metals.
Formulas of ionic compounds.
Naming simple compounds.
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Forming a Cation
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Forming an Anion
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Using The Periodic Table
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Three Types of Binary Compounds
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Metal (Groups 1,2, 3) and nonmetal
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Metal (transition) and nonmetal
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Simple naming: sodium chloride [NaCl].
Roman numerals: cobalt(II) chloride [CoCl2].
Two nonmetals
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Prefixes: carbon dioxide [CO2].
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Three Types of Binary
Compounds
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Na2O
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Cu2O
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N2O
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Type I Compound
Na2O
sodium oxide
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Type II Compound
Cu2O
copper(I) oxide
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Type III Compound
N2O:
dinitrogen
monoxide
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Type III Compound
N2O5
dinitrogen pentoxide
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Clicker Question
How many of the following is/are named
incorrectly?
I. PCl3 phosphorus(III) chloride
II. KCl potassium monochloride
III. CoO cobalt oxide
IV. Fe2O3 iron(II) trioxide
a) 0
b) 1
c) 2
d) 3
e) 4
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Clicker Question
These are correct:
I. PCl3 phosphorus trichloride
II. KCl potassium chloride
III. CoO cobalt(II) oxide
IV. Fe2O3 iron(III) oxide
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Clicker Question
The mass of a single atom of hydrogen is:
a) 1.008 g
b) 2.016 g
c) 1.000 mole
d) 1.674 x 10-24 g
e) 6.022 x 1023 g
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Clicker Question
You have a 12.01 g sample of carbon and a
1.008 gram sample of hydrogen.
a) The number of carbon atoms is greater than
the number of hydrogen atoms.
b) The number of carbon atoms is less than the
number of hydrogen atoms.
c) The number of carbon atoms is the same as
the number of hydrogen atoms.
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The Mole Concept: Why?
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We can count by weighing (relative
masses).
Reactions occur by number of particles,
we must deal with masses, so we must
have a way of converting between
number and mass.
Atoms/molecules are very small!
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Clicker Question
You have equal mass samples of copper (Cu)
and magnesium (Mg). Which sample contains
the greater number of atoms?
a) The sample of magnesium.
b) The sample of copper.
c) The samples contain the same number of
atoms.
d) I have no idea.
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A Question For You…
You have a 10.0 g sample of copper
(Cu).
Determine the mass of magnesium
(Mg) such that the number of copper
atoms equals the number of
magnesium atoms.
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A Question For You…
You have 50.0 g of water.
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How many moles of H2O molecules
do you have?
How many moles of hydrogen atoms
are present in this sample?
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