Pen or Pencil Piece of paper TAKE NOTES ON PAGE 3

What is a SOLUTION ?

What is a SOLUTE ?

 Solute is a substance being dissolved. Hint: it is usually present in smaller amount SUGAR

 What is a SOLVENT ?

Solvent is the substance that dissolves the solute. Hint: it is usually present in the greater amount. WATER

+ = +(tea)

10 Which mixture can be separated by using the equipment shown? (1) NaCl(aq) and SiO 2 (s) (2) NaCl(aq) and C 6 H 12 O 6 (aq) (3) CO 2 (aq) and NaCl(aq) (4) CO 2 (aq) and C 6 H 12 O 6 (aq) (aq) stands for aqueous which means dissolved in water. Dissolved particles are too small to be trapped by the filter.

 Solubility : Maximum quantity of solute that can dissolve in an amount of solvent at a specified temperature  Measured in grams (solute) /grams (solvent)

 Rate of Solution: measure of how fast a substance dissolves

 Size of Particles: (solid solute) As surface area  rate of solution  To increase surface area, crush large crystals Example: sugar granules vs. sugar cubes

 Stirring: Makes solute come in contact with solvent  Amount of solute in solution: The less solute in solution the faster more will dissolve.

 Temperature: For liquids/solids: As T  Rate of Soln.  For gases: As T  Rate of Soln. 

 Nature of solute and solvent: “Like dissolves like” polar solutes dissolve in polar solvents example: ionic solids in water non polar solutes in non polar solvents

 Temperature: For Ionic solids: as T  solubility  example: Jell-O in boiling water For gases: as T  solubility  example: warm soda goes flat

 Pressure: For solids/liquids: As P changes, solubility does not change For gases: as P  solubility  Effervescence: escape of gas from soln.

 Solubility is the maximum amount of solute that a solvent can hold at a given temperature.  An unsaturated solution is one in which the solvent can dissolve more solute  A saturated solution is one in which the solvent has as much solute as it can hold  A supersaturated solution is one in which there is more solute dissolved than a solvent can normally hold.  Make a supersaturated solution by cooling a saturated solution  Supersaturated solutions are unstable and will precipitate the excess solute when a seed crystal is added. 19

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25 Table G shows the solubility of some gases and solids at various temperatures when dissolved in 100 grams of water.

26 A solution which is on the line is saturated A solution below the line is unsaturated A solution above the line is supersaturated

 Unsaturated – the test crystal dissolves  Saturated – the test crystal settles to the bottom  Supersaturated – a large amount of crystals precipitate from the solution 27

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29 According to Reference Table G, which solution is saturated at 30°C? (1) 12 grams of KClO 3 in 100 grams of water (2) 12 grams of KClO 3 in 200 grams of water (3) 30 grams of NaCl in 100 grams of water (4) 30 grams of NaCl in 200 grams of water

30 One hundred grams of water is saturated with NH 4 Cl at 50°C. According to Table G, if the temperature is lowered to 10°C, what is the total amount of NH 4 Cl that will precipitate? (1) 5.0 g (3) 30. g (2) 17 g (4) 50. g

31 When cola, a type of soda pop, is manufactured, CO 2 (g) is dissolved in it. A capped bottle of cola contains CO 2 (g) under high pressure. When the cap is removed, how does pressure affect the solubility of the dissolved CO 2 (g)? A glass of cold cola is left to stand 5 minutes at room temperature. How does temperature affect the solubility of the CO 2 (g)? As the pressure decreases, the solubility decreases. As the temperature increases, the solubility decreases.

32 Hexane (C 6 H 14 ) and water do not form a solution. Which statement explains this phenomenon? (1) Hexane is polar and water is nonpolar. (2) Hexane is ionic and water is polar. (3) Hexane is nonpolar and water is polar. (4) Hexane is nonpolar and water is ionic.

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 Soluble will dissolve  Insoluble will not dissolve 34

 Not all substances are soluble in water  Reference Table F lists solubility rules and exceptions to those rules. 35

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37 Which of the following compounds is least soluble in water? (1) copper (II) chloride (2) aluminum acetate (3) iron (III) hydroxide (4) potassium sulfate

38 According to Table F, which of these salts is least soluble in water? (1)LiCl (2) RbCl (3) FeCl 2 (4) PbCl 2

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 The concentration of a solution is a measurement of the amount of solute dissolved in solution.  Dilute is very little solute  Concentrated is at or near saturation  Molarity is a [concentration] of moles/liter  Table T

42 What is the molarity of a solution that contains 0.50 mole of NaOH in 0.50 liter of solution? (1) 1.0 M (3) 0.25 M (2) 2.0 M (4) 0.50 M Molarity = Moles Liters

43 How many moles of solute are contained in 200 milliliters of a 1 M solution? (1) 1 (3) 0.8 (2) 0.2(4) 200

44 What is the total number of grams of NaI(s) needed to make 1.0 liter of a M solution? (1) (3) 1.5 (2) 0.15 (4) 15 Na 1 x 23.0 = 23.0 I 1 x = g / mole Molarity = moles liters 0.010M = x 1.0 L X = moles moles x g/mole =

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 Parts per million ppm is often used to measure concentrations of solutes that are present in very small amounts Parts Per Million = Mass of Solute Mass of Solution X 1,000,000

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 Some properties (like boiling point and melting point) of substances change when non-volatile substances are added.  We add salt to ice and lower the freezing point. The ice melts and we are safe. YAY!!!!!!  Rule #1 – The more dissolved particles, the greater the effect on FP and BP  Rule #2 – Ionic substance dissociate so will tend to effect FP and BP greater.

 Non-electrolytes are molecular substances that do not break up into ions (i.e. sugar)  C 12 H 22 O 11  C 12 H 22 O 11 (aq) 1 mole1 mole

 Electrolytes are ionic substances that break up into ions when put in solution. (ex: NaCl)  NaCl  Na + + Cl - 1 mole NaCl  1mole Na mole Cl - Because there are more moles produced, this has a greater effect on colligative properties.

 Which will have the lowest freezing point?  Which will have the highest freezing point? 1 mole of MgCl 2 in 500 g water 1 mole of C 6 H 12 O 6 in 500 g water Freezing point will always be lower than 0°C.

 Boiling point is raised when a non-volatile substance is added.  Example: water boils at a higher temp when salt is added

 Which will have the highest boiling point?  Which will have the lowest boiling point? 1 mole of MgCl 2 in 500 g water 1 mole of C 6 H 12 O 6 in 500 g water Boiling point will always be higher than 100°C.

57 At standard pressure when NaCl is added to water, the solution will have a (1) higher freezing point and a lower boiling point than water (2) higher freezing point and a higher boiling point than water (3) lower freezing point and a higher boiling point than water (4) lower freezing point and a lower boiling point than water

58 Compared to pure water, an aqueous solution of calcium chloride has a (1) higher boiling point and higher freezing point (2) higher boiling point and lower freezing point (3) lower boiling point and higher freezing point (4) lower boiling point and lower freezing point

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