solutions mixtures (varied ratio) homogeneous true solutions (soluble) solubility – ability to...

Solutions

Mixtures(Varied Ratio)

Homogeneous• True Solutions (Soluble)• Solubility – Ability to

dissolve in solution• (aq) See only 1 part• Separated by evaporation• Contains 2 Parts

1. Solute – The substance that is being dissolved

2. Solvent – What is doing the dissolving (Water)

Heterogeneous• See Multiple parts• Sand/ water, Dirt, Rocky

road ice cream• Separated by filtration

Factors that effect Solubility

1. Pressure (g only) - P Solubility2. Agitation – stirring (s) will Solubility3. Nature of Solvent /solute

1. “Like dissolves like”1. Water (polar) will dissolve Salts (Ionic-polar)2. Water (Polar) does not dissolve fats –oils

(non-polar)4. Temperature - T Solubility (solids only)

T Solubility (Gas…think soda)

P A N T

3 Types of SolutionsUnsaturated, Saturated and Supersaturated

Table G

All BASED ON 100g OF WATER as the SOLVENT

Unsaturated 1. A solution that contains less solute than it

can actually hold at any given temperature

2. Said to be “below the line”

X

3 Types of SolutionsUnsaturated, Saturated and Supersaturated

Table G

Saturated 1. A solution that contains the Maximum

amount of solute that it can actually hold at any given temperature

2. Said to be “on the line”

X

Saturated 1. A solution that contains the Maximum amount

of solute that it can actually hold at any given temperature

2. Said to be “on the line”3. If more solute is present, a precipitate (ppt) will

form on the bottom4. Seen ONLY in saturated Solutions

XProblem:At 60’C, 128 g of NaNO3 will dissolve in 100g of water. If this sample of water is cooled to 35 ‘C, How much NaNO3 will still be dissolved in the water?

How much ppt will form?

3 Types of SolutionsUnsaturated, Saturated and Supersaturated

Table G

Super Saturated 1. A solution (Forced) that contains

More solute than it can actually hold at any given temperature

2. Said to be “above the line”

X

Making a Super Saturated Solution

Phase EquilibriumSeen only with Saturated Solutions

Rate of dissolving = Rate of Crystalizing

Phase EquilibriumSeen only with Saturated Solutions

Table G - Solubility Curves

1. All based on 100g of Water as the Solvent2. So…. If you have 200 g of water, you must

double all the values3. If you have 300g of water, _______________________________4. If you have 50g of water , _______________________________

Concentration1. Measured by Molarity

1 Gram of H2O = 1ml 1L = 1000ml

Parts Per Million (ppm) = Mass of solute x 1,000,000 Mass of Solution

Below are the two equations needed to perform the concentration calculations needed for the first 12 questions of this sheet. You may recognize them from the back cover of your Reference Tables.

What is the molarity of a solution which has a total volume of 100 mL and contains 3 moles of NaCl?

What is the molarity of a solution that contains 1.5 moles of NaNO3 in 2.5 Liters of solution?

A solution is made that contains 1.25 moles of sugar in 175 mL of solution. What is the molarity of the solution?

A 4 molar solution of ammonium chloride will contain how many moles of solute in 100 mL of solution?

Given a 250 mL sample of a solution that is 0.25 molar, how many moles of the solute do you possess?

How many moles of KNO3 are needed to make 0.750 L of a 3.25 M solution?

What volume of solution, measured in liters, is necessary to obtain 1 mole of solute if the concentration of the solution is 1.25 M?

If a sample of solution contains 1.5 moles of sodium hydroxide, and the concentration of the solution is 0.8 M, then what volume of the solution do you possess?

Given a 1.4 M NaCl solution, 0.90 moles of sodium chloride would be contained in how many milliliters of the solution?

If you have made a 455 ppm solution, how many grams of sodium chloride are in 1000 grams of the solution?

When 0.0043 grams of O2 is dissolved in 100 mL of water, what is the concentration of the solution, measured in ppm?

A substance has a solubility of 350 ppm. How many grams of the substance are present in 1.5 L of solution?

%100*_

_%

solutionvolume

solutevolumeVolume

%100*_

_%

wholeMass

partMassmass

13. What is the percent by volume of ethanol if 50.0 mL of ethanol is diluted with water to form a total volume of 300.0mL?

14. How many milliliters of a liquid were used to make a 13% solution with a total volume of 80 mL?

15. What volume of a 35% solution of alcohol can be made using 20 mL of the solute?

16) A rock contains 15 grams of calcium carbonate and 85 grams of other substances, what is the composition of the rock as measured in percent by mass?

Molarity by Dilution

1. Done using the Titration equation but make a change!

M1V1 = M2V2

Electrolytes

• Substances that when put into solution, will dissociate in solution

• DISSOCIATION – the ability to break up into their component ions in solution

• It is the “Mobile Ions” that give the solution the ability to conduct electricity

• Ionics (Polar Substances) have this ability• Good Electrolytes (Salts, Acids and Bases)• Non-electrolytes (covalent compounds)

H

HO Na+Cl-

Remember Molecule – Ion Attraction

• This is why Polar substances like ionic compounds dissolve in and dissociate in water (polar)!

What other type of attraction do you see at work here?

Colligative Properties