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					Ch. 4

4.1- The Role of Water as a Solvent
Water’s solvent capabilities come from its ____________ of the bonding __________ and the
overall ________.

Electrons in a covalent molecule are _________.

A polar molecule results from an _________ distribution of charge due to the distribution of
_______ clouds around the molecule. This causes polar molecules to ______ other charged
In a water molecule, the ___ atom(s) are slightly positive, and the ___ atom(s) are slightly

Activity: Draw a water molecule with the correct shape. Then label the molecule with δ+ and
δ-. Then give the overall polar arrow.

Ionic Compounds in Water
Water _______ the ions by replacing that _______ with one between the water molecules and
the ions.

Activity: Explain in your own words how a solute is dissolved in water.

Conducting Electricity
Electrical Conductivity is the ______ of electric ________.

When a(n) ______(pick covalent or ionic) substance is dissolved it creates a ________ of
charged particles.

A substance that conducts a current when dissolved in water is an ___________.
________ (type of bond) compounds and ______ (state of matter) compounds do not conduct
Aqueous solutions that do not conduct an electric current are called __________.

Activity: Fill in the blank with the following words- electrolyte, strong, weak, conduct, solid,
ionic, covalent
    1) Pure water does not _______ electricity.
   2) _____ KBr will not conduct electricity.
   3) CH4 is a _______ molecule and will not conduct electricity.
   4) A _______ is a substance that conducts electricity when dissolved in water.

4.2 Writing Equations for Aqueous Ionic Reactions
The molecular equation shows all the reactants and _________ as if they were intake,
_________ compounds.
Example: 2 AgNO3 (aq) + Na2CrO4 (aq) Ag2CrO4 (s) + 2 NaNO3

The total ionic equation show all the _______ ionic substances dissociated into ions.
Example: 2Ag+ (aq) +2NO3- (aq) +2Na+ (aq) + CrO42- (aq) Ag2CrO4 (s) + 2Na+ (aq) +2NO3- (aq)

The _______ ions appear on ______ sides of the equation because they are not ________ in
the actual chemical change.
The net ionic equation omits the _______ ions and shows the actual chemical change taking
example: 2Ag+ (aq) +CrO42- (aq)  Ag2CrO4 (s)

Activity: Give the Molecular, Total Ionic, and Net Ionic equations for the following equation.
Remember: to balance, to carry coefficients and correct number of ions, and to always write
the states
FeCl3 (aq) + Cs3PO4 (aq) FePO4 (s) + CsCl (aq)

4.3 Precipitation Reactions
A precipitation reaction is when two _______ ionic compounds reacts to form an __________
product called a ________.
This is the formation of an ________ product through the net removal of _________ ions from
There are two things you will have to do: Predict the products and know if they are aqueous
(soluble) or solid (insoluble).
Ionic compounds are made up of partners, a ______ charged cation and a ______ charged
anions. In a reaction, the compounds will ________ and repartner-up with a different partner.

Activity: Predict the products and write the states using the solubility rules.
   1) Sodium hydroxide (aq) + cadmium nitrate (aq) 
   2) Magnesium bromide (aq) + potassium acetate (aq) 

4.4 Acid- Base Reactions
An acid-base reaction occurs when an ______ reacts with a _______.
An ______ is a substance that produces H+ ions when dissolved in ______.
A ______ is a substance that produces OH- ions when dissolved in _______.
Strong acids and strong bases dissociate _______ into ions, so they are ______ electrolytes.
Weak acids and weak bases dissociate into ions very ______, and most other their ________
remain intact, so they conduct only a ______ electric current and are ______ electrolytes.

Activity: List weak and strong acids and weak and strong bases.

Activity: Fill in either a single headed arrow or a double headed arrow where appropriate.
ex. HCl + H20 Cl- (aq) + H+ (aq)

NaOH + H2O     Na+ (aq) + OH- (aq)
CH3COOH + H2O     CH3COO- (aq) + H+ (aq)
HClO4 + H2O    +
              H (aq) + ClO4- (aq)
NH3 + H2O   NH4+ (aq) + OH- (aq)

The essential change in all aqueous reactions between a strong acid and a strong base is that an
____ ion from the acid and an ____ ion from the base form a water molecule. The biproduct is
an ionic compound called a _______.
HX (aq) + MOH (aq)  MX (aq) + H2O (l)
acid      base         salt      water

Activity: Write your own example of an acid-base reaction.

A titration is when one solution of ______ concentration is use to determine the __________ of
another solution through a monitored reaction.

4.5 Redox Reactions
In oxidation-reduction reactions, the key chemical event is the net ________ of electrons from
one reactant to the other. There is a ________ of electrons.
Oxidation is the ______ of electrons and the oxidation number goes ______.
Reduction is the ________ of electrons and the oxidation number goes ______.
The ______ agent does the oxidizing so it is also the one being reduced.
The ______ agent does the reducing so it is also the one being oxidized.
The method chemists use to monitor which atom loses electron charge and which gains is
assigning an _______ _______.

Activity: Assign Oxidation Numbers, states, predict products, and determine if it is a redox-
reaction or not.
Ex. NCl3 + H2O 
NCl3 (l) + 3H2O (l)  NH3 (aq) + 3HOCl (aq)
+3 -1      +1 -2     -3 +1       +1 -2 +1
N goes from +3 to -3, it is reduced.
Cl goes from -1 to +1, it is oxidized.
This is a redox reaction.

AgNO3 + K2CO3 

KCl + AgNO3 

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