Solutions Worksheet 1 -- Chapter 13 Part III Coming to Terms with

Transcription

Solutions Worksheet 1 -- Chapter 13 Part III Coming to Terms with
Name:
Chapter 14 Solutions
Section:
Date:
Solutions Worksheet 1
Calculating Solution Concentrations
A solution is a physical mixture of at least two pure substances. Any of the three phases can
be mixed in each other to achieve a solution.
 Give an example of a solid/liquid solution
 Give an example of a gas/liquid solution
Define Solute –
Define Solvent –
Define Solution –
Draw a picture of solute + solvent = solution
Molarity = moles of solute
Liters of solution
+
=
 Molarity Problems: List given information, use conversion factor, include units.
1. What would be the molarity of a solution if you dissolved 2 moles of NaCl in 6 liters of
solution?
2. How many moles of HCl are present in 10 liters of 2.0M HCl?
3. What volume of calcium sulfate, CaSO4, would you need if you dissolved 4 moles of it to
make a 0.1M solution?
4. What is the mass of solute in 61.8 ml of 1.03M LiCl?
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5. Calculate the mass of solute required to make 1 liter of each of the following:
a.) 0.925 M NaNO3
b.) 2.12 M NaOH
c.) 0.965 M LiNO3
6. Calculate the concentration of each of the following solutions using Molarity.
a.)
200 ml of solution containing 8.31 g of LiNO3
b.)
750 ml of solution containing 0.00641 g of AgNO3
7. 3 grams of potassium sulfate is dissolved into 2 liters of solution. What is the molarity?
8. What would be the molar mass of an unknown salt if 11.70 grams dissolved in 2 liters of
solution give a 0.1 M solution?
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Chapter 14 Solutions
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Refer to this Solubility Chart when answering the solubility
questions in Worksheet #2
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Chapter 14 Solutions
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Solutions Worksheet 2 -- Chapter 14 Coming to Terms with Solutions - Using a solubility chart
provided answer each of the following:
1. What solvent is used to dissolve the four compounds?
2. Are KNO3, NaCl, NaNO3 and NH4Cl miscible with water at temperatures from 0C to 100C?
3. What is the solubility of KNO3 at 0C? (make sure to report units)
4. What is the solubility of NaNO3 at 10C?
5. If a solution at 50C contains 50g of the solute NH4Cl in 100g of water, is the solution saturated,
unsaturated, or supersaturated?
6. What would you see happening if a solution containing 80g of KNO3 in 100g of water at 50C
cooled to 30C?
7. Describe the cooled solution of KNO3 as saturated, unsaturated, or supersaturated.
8. Which of the four substances has the greatest solubility at 0C?
9. Which substance, Li2SO4 or KNO3 has the greater solubility at 10C? Which has the greater
solubility at 70C?
10. What two processes take place when each of the four substances dissolves in water?
11. Diagram (draw a picture of) each of the processes for NaCl in water:
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Chapter 14 Solutions
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Solutions Worksheet 3
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Using a Solubility Table
 This activity will help you to become efficient in using the solubility table to determine
whether an ionic compound is soluble or insoluble.
 To determine the solubility of an ionic compound, locate the compound’s negative ion in the
first column of the solubility table.
 Find the positive ion or the group in which the positive ion belongs.
 Determine whether the compound is soluble or insoluble. Practice using the chart by
determining if each of the following compounds will dissolve in water.
 Then write the correct form for the compound in water:
 If a compound dissolves, write the ions formed (in aqueous solution)
 If it does not dissolve, write in molecular formula for the compound
Example:
1. NaCl (s)
 Na+1(aq) + Cl-1(aq)
2.
KCH3COO(s) 
3.
AgNO3(s)

4.
Fe(OH)2(s)

5.
SnBr4(s)

6.
Na2CrO4(s)

7.
ZnS(s)

8.
(NH4)2CO3(s) 
9.
Li(OH)(s)

10.
PbCl2(s)

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Solutions Worksheet 4 - Writing Net Ionic Equations (you will need to be able to do this on
the test)
A complete ionic equation shows all of the reactants and products in correct solution
form.
A net ionic equation shows
o Only the reacting species in a chemical reaction, and
o Does not include spectator ions.


First write a balanced complete equation, showing all reactants and products in correct
form.
Then write a balanced net ionic equation. Cross out the spectator ions from the
complete equation. Include only the reacting species on the reactant and product sides.
1. Sodium hydroxide and iron (III) chloride, give sodium chloride and iron (III) hydroxide.
Complete ionic equation:
Net ionic equation:
2. Potassium sulfide and copper (II) nitrate, give potassium nitrate and copper (II) sulfide.
Complete ionic equation:
Net ionic equation:
 Determine the correct precipitate formed for each of the following reactions:
3. Ammonium sulfate reacts with barium chloride.
Complete ionic equation:
Net ionic equation:
4. Lithium phosphate reacts with calcium bromide.
Complete ionic equation:
Net ionic equation:
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Solutions Worksheet 5
Molality and Colligative Properties
 The addition of a(n)
and
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to a pure liquid solvent changes the
of the liquid.
 The vapor pressure, boiling point, and freezing point of a solution are
properties and depend upon the
rather than on their
 The
of solute particles
.
of a liquid is related to the tendency of the molecules to
escape from a solution. For example, the proportion and escaping tendency of water
molecules is
when a solute is dissolved in pure water, and the vapor
pressure of the solution is therefore
than that of pure water.
What is the equation for calculating boiling point elevation?
What is the equation for calculating freezing point depression?
 Determine the molality, and freezing point of the following solutions:
1. 50 g sucrose, C12H22O11, in 200 g water.
2. 100 g glycerol, C3H8O3, in 200 g water
3. 35 g sodium chloride, NaCl, in 200 g water
4. 18 g ammonium phosphate, (NH4)3PO4 200 g water.
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Solutions Worksheet 6 --
Converting Concentrations
Mass of solvent
Mass of solute
MolaLity
Molar mass
Moles of solute
Mass of solution = solute + solvent
Density of solution
MolaRity
Volume of solution
5. Describe what you would do to prepare 100.0 gram of a 3.5% solution of ammonium sulfate
in water.
6. What is the Molarity of this solution? Assume the density is 1.0 g/ml.
7. What is the molality, and boiling point of this solution?
Dilution Problems: Are based on the fact that the original moles of solute are equal to the final
moles of solute. Rearrange the equation to solve for the missing quantity.
M1V1 = M2V2
8. What is the molarity of a solution of ammonium chloride prepared by diluting 50.00 mL of a
3.79 M NH4Cl solution to 2.00 L?
9. To what volume should 1.19 mL of an 8.00 M acetic acid solution be diluted in order to
obtain a final solution that is 1.5 M?
10. A 25.00 mL sample of ammonium nitrate solution produces a 0.186 M solution when diluted
with 50.00 mL of water. What is the molarity of the stock solution?
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