# Solutions.

## Presentation on theme: "Solutions."— Presentation transcript:

Solutions

Mixtures (Varied Ratio)
Homogeneous Heterogeneous True Solutions (Soluble) Solubility – Ability to dissolve in solution (aq) See only 1 part Separated by evaporation Contains 2 Parts Solute – The substance that is being dissolved Solvent – What is doing the dissolving (Water) See Multiple parts Sand/ water, Dirt, Rocky road ice cream Separated by filtration

Factors that effect Solubility
P A N T Pressure (g only) P Solubility Agitation – stirring (s) will Solubility Nature of Solvent /solute “Like dissolves like” Water (polar) will dissolve Salts (Ionic-polar) Water (Polar) does not dissolve fats –oils (non-polar) Temperature T Solubility (solids only) T Solubility (Gas…think soda)

3 Types of Solutions X Unsaturated, Saturated and Supersaturated
Table G All BASED ON 100g OF WATER as the SOLVENT Unsaturated A solution that contains less solute than it can actually hold at any given temperature Said to be “below the line” X

3 Types of Solutions X Unsaturated, Saturated and Supersaturated
Table G Saturated A solution that contains the Maximum amount of solute that it can actually hold at any given temperature Said to be “on the line” X

Saturated A solution that contains the Maximum amount of solute that it can actually hold at any given temperature Said to be “on the line” If more solute is present, a precipitate (ppt) will form on the bottom Seen ONLY in saturated Solutions Problem: 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? X

3 Types of Solutions X Unsaturated, Saturated and Supersaturated
Table G Super Saturated A solution (Forced) that contains More solute than it can actually hold at any given temperature Said to be “above the line” X

Making a Super Saturated Solution

Seen only with Saturated Solutions
Phase Equilibrium Seen only with Saturated Solutions Rate of dissolving = Rate of Crystalizing

Phase Equilibrium Seen only with Saturated Solutions

Table G - Solubility Curves
All based on 100g of Water as the Solvent So…. If you have 200 g of water, you must double all the values 3. If you have 300g of water, _______________________________ 4. If you have 50g of water ,

Concentration 1. Measured by Molarity 1 Gram of H2O = 1ml 1L = 1000ml
Parts Per Million (ppm) = Mass of solute x ,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
How many moles of KNO3 are needed to make 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
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 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?

13. What is the percent by volume of ethanol if 50
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?

M1V1 = M2V2 Molarity by Dilution
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)

Remember Molecule – Ion Attraction
H O Na+ Cl- H 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