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IPS
NAME
Chapter 4 Review
DATE
PERIOD
1. Be sure the definitions the following terms are in your glossary and that you understand each.
Solute
Unsaturated
Solvent
Concentration
Solution
Solubility
Precipitate
Soluble
Saturated
Insoluble
2. When a substance such as an orange solid dissolves in water, what happens to it? Where can the
solute be found?
3. As more orange solid is added, and the solution is stirred, what happens?
For all problems-show your work, include units in work and answer, and follow sig dig rules.
4. A mass of 16 g of salt is mixed with 62 mL of water. What is the concentration of the solution?
5. How much water is needed to make a sugar solution with a concentration of 217 g/100 cm3,
if 58 g of sugar is used?
6. A solution contains 112 g of sodium sulfate in 636 mL of water. If you want to make a solution with
the same concentration, but must use 192 mL of water, how much sodium sulfate is needed?
7. Use the following data to calculate the solubility of unknown X. Show your work.
Mass of evap. dish and watch glass
32.70g
Mass of evap. dish, watch glass, and solution
46.53g
Solubility =
Mass of evap. dish, watch glass, and solid
39.17g
1
Mass of
evap. dish
and watch
glass (g)
2
Mass of evap.
dish, watch
glass and
solution (g)
3
(2-1)
Mass of
solution
(g)
4
Mass of
evap. dish,
watch glass
and solid (g)
5
(4-1)
Mass of
solid (g)
1
6
(3-5)
Mass of
solvent
(g)
7
(7=6)
Volume
of solvent
(cm3)
8
(5 ÷ 7)
Concentration
(g/cm3)
9
(8 x 100)
Solubility
(g/100cm3)
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Refer to your solubility graph handout or page 74 in your text for questions 8-18. Show work.
8. What is the solubility of potassium nitrate ate 45 °C?
9. Which substance is most soluble at 65 °C?
10. Which substance is least soluble at 65 °C?
11. How much sodium nitrate would you need to have a perfectly saturated solution at 50 °C?
12. What is the lowest temperature 120 g of sodium nitrate will all dissolve?
13. A mass of 30 g of potassium nitrate is dissolved in 100 mL of water at 10ºC. The solution is heated
to 80ºC. How much more solid needs to be added to keep the solution saturated?
14. A mass of 160 g of sodium nitrate is dissolved in 100 mL of water at 100ºC. The solution is cooled.
At what temperature should a precipitate form?
15. How much sodium nitrate will precipitate out of solution if you cool a saturated solution from 80 °C
to 20 °C?
Are the following solutions saturated or unsaturated?
16. 50 g of potassium nitrate at 80 °C?
17. 100 g of sodium nitrate at 30 °C?
***18. If you dissolve 30 g of potassium nitrate in 25 mL of water and then heat it to 80 °C, how much
solid should you add to keep the solution saturated?
19. Using the information in the table below: Are wood alcohol and grain alcohol the same substance?
Explain.
Alcohol Type
Wood Alcohol
Grain Alcohol
Density (g/100 cm3) M.P. (ºC)
.79
-98
.79
-117
20. What are the chemical names for
wood alcohol?
B.P. (ºC)
64.7
78.5
grain alcohol?
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The following data was gathered at 30ºC to find the solubility of the two substances.
The table below shows the maximum amount of each solute (washing soda and baking soda) that would
dissolve in the volume of solvent given. Answer questions 21-23 using this information.
Substance
Solute (g)
Solvent (mL)
220
1000
Washing Soda
24
350
Baking Soda
21. Which substance has a higher solubility (g/100mL)? Show work.
22. What is meant by ‘higher solubility”?
23. What is the largest mass of each substance that will dissolve in 60 mL of water? (show work)
Washing sodaBaking soda-
24. If 6.7 g of a substance will dissolve in 57.3 mL of water at 40ºC, what is the solubility at that
temperature?(show work)
25. The following table shows the solubility of carbon dioxide (CO2) at various temperatures.
Graph the data.
Temperature (ºC)
Solubility (g/100 mL)
0
10
20
30
40
50
60
.34
.24
.18
.14
.12
.10
.08
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Using the graph in problem #25 on the previous page, answer the following questions:
a. How much CO2 will dissolve in 100 cm3 of water at 25ºC?
b. Approximately how much CO2 will dissolve in 100 cm3 of water at 70ºC?
c. How much CO2 will dissolve in 50 cm3 of water at 30ºC? (show work)
26. If you had to collect a gas by water displacement, would it be better to collect the gas at cooler or
warmer temperatures? Explain.
27. Sketch a curve showing how increasing temperature would affect the solubility of
solids?
gases?
28. When a test tube of ammonia gas is inserted into a beaker of water already saturated with ammonia,
would water go up into the test tube? Why or why not?
29. Can water displacement be used to collect a highly soluble gas like ammonia? Why or why not?
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