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Chapter 4
 Homework
 You will need to read these
sections and take notes. If
you have questions while
reading, write them in your
notes and then ask tomorrow.
 Chemical reactions often take place
when two solutions are mixed. To
perform stoichiometric calculations
we must know TWO things:
 1. The nature of the reaction (what
happens)
 2. Amounts of chemicals present
(usually expressed in molarity)
 Molarity (M)= moles solute per liter
of solution
 Exercise 4.1
 Calculate the molarity of a solution
prepared by dissolving 11.5g of
solid NaOH in enough water to
make 1.50L of solution.
0.192M
Calculate the molarity of a
solution prepared by
dissolving 1.56g of HCl in
enough water to make
26.8mL of solution.
1.60M
Give the concentration
of each type of ion in
the following solutions
A. 0.50M Co(NO3)2
B. 1M Fe(ClO4)3
A.
+2
0.5oM Co ,
B.
+3
Fe ,
1M
1.0M NO3
3M ClO4
-
Calculate the number of
moles of chloride ions in
1.75L of 0.001M zinc
chloride.
0.004mol Cl
Typical blood serum is
about 0.14M NaCl.
What volume of blood
contains 1.0mg NaCl?
0.12mL blood
 To analyze the alcohol content of
a certain wine, a chemist needs
1.00L of an aqueous 0.200M
K2Cr2O7 solution. How much
potassium dichromate must be
weighed out to make this
solution?
Read and Study p. 143
We will make a solution
tomorrow!
 How do you dilute a solution?
 How do you calculate the
concentration of a diluted solution?
 How can you determine the volume
of stock solution you need to make a
desired dilute solution?
What volume of 16M
sulfuric acid must be
used to prepare 1.5L of
a 0.10M sulfuric acid
solution?
9.4mL
 Precipitation reactions
 Acid-Base reactions
 Oxidation-reduction reactions
(Redox)


When two solutions are mixed, an insoluble
solid sometimes forms (precipitate)
Example:
 Barium nitrate reacts with potassium
chromate
▪ What are the products?
▪ Which product is the precipitate?
LEARN THEM!!
p.150 or in summer
assignment info!!




Using the solubility rules predict what will
happen when the following pairs of solutions
are mixed:
A. Potassium nitrate & Barium Chloride
B. Sodium sulfate & Lead (II) nitrate
C. Potassium hydroxide & iron (III) nitrate
 A.
No reaction
 B. Lead (II) sulfate
 C. Iron (III) hydroxide
Molecular equation: shows reactants
and products
 Complete Ionic equation: represents
the actual forms of the reactants and
products in solution
 Net Ionic equation: includes only those
solution components directly involved in
the reaction.


Write the molecular equation, the
complete ionic equation, and the net
ionic equation

A. Aqueous potassium chloride is added
to aqueous silver nitrate to form a silver
chloride precipitate plus aqueous
potassium nitrate.
 B.
Aqueous potassium hydroxide
is mixed with aqueous iron(III)
nitrate to form a precipitate of
iron(III) hydroxide and aqueous
potassium nitrate.
 Calculate the mass of solid
NaCl that must be added to
1.50L of a 0.100M AgNO3
solution to precipitate all the
+
Ag ions in the form of AgCl.
8.77g NaCl
 When aqueous solutions of Na2SO4
and Pb(NO3)2 are mixed, PbSO4
precipitates. Calculate the mass of
PbSO4 formed when 1.25L of
0.0500M Pb(NO3)2 and 2.00L of
0.0250M Na2SO4 are mixed.
15.2g PbSO4
What volume of 0.50M sulfuric acid is required
to neutralize 50.0mL of 1.45M aluminum
hydroxide?
Answer: 220mL
What mass of chloric acid would be needed to
completely neutralize 50.0g of magnesium
hydroxide?
Answer: 51.1g