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SolutionsSAVE PAPER AND INK!!! When you print out the notes on PowerPoint,

print "Handouts" instead of "Slides" in the print setup. Also,

turn off the backgrounds (Tools>Options>Print>UNcheck

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Some DefinitionsA solution is a mixture

of 2 or more substances in a single phase.

One constituent is usually regarded as the SOLVENT and the others as SOLUTES.

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Parts of a Solution• SOLUTE – the

part of a solution that is being dissolved (usually the lesser amount)

• SOLVENT – the part of a solution that dissolves the solute (usually the greater amount)

• Solute + Solvent = Solution

Solute Solvent Example

solid solid

solid liquid

gas solid

liquid liquid

gas liquid

gas gas

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Definitions

Solutions can be classified as saturated or unsaturated.

A saturated solution contains the maximum quantity of solute that dissolves at that temperature.

An unsaturated solution contains less than the maximum amount of solute that can dissolve at a particular temperature

5Example: Saturated and Unsaturated Fats

Unsaturated fats have at least one double bond between carbon atoms; monounsaturated means there is one double bond, polysaturated means there are more than one double bond. Thus, there are some bonds that can be broken, chemically changed, and used for a variety of purposes. These are REQUIRED to carry out many functions in the body. Fish oils (fats) are usually unsaturated. Game animals (chicken, deer) are usually less saturated, but not as much as fish. Olive and canola oil are monounsaturated.

Saturated fats are called saturated because all of the bonds between the carbon atoms in a fat are single bonds. Thus, all the bonds on the carbon are occupied or “saturated” with hydrogen. These are stable and hard to decompose. The body can only use these for energy, and so the excess is stored. Thus, these should be avoided in diets. These are usually obtained from sheep and cattle fats. Butter and coconut oil are mostly saturated fats.

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Definitions

SUPERSATURATED SOLUTIONS contain more solute than is possible to be dissolved

Supersaturated solutions are unstable. The supersaturation is only temporary, and usually accomplished in one of two ways:

1. Warm the solvent so that it will dissolve more, then cool the solution

2. Evaporate some of the solvent carefully so that the solute does not solidify and come out of solution.

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SupersaturatedSodium Acetate

• One application of a supersaturated solution is the sodium acetate “heat pack.”

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Concentration of SoluteConcentration of Solute

The amount of solute in a solution is given by its concentration.

Molarity (M) = moles soluteliters of solution

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1.0 L of water was

used to make 1.0 L of solution. Notice the water left

over.

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PROBLEM: Dissolve 5.00 g of NiCl2•6 H2O in enough water to make 250 mL of solution. Calculate the Molarity.

PROBLEM: Dissolve 5.00 g of NiCl2•6 H2O in enough water to make 250 mL of solution. Calculate the Molarity.

Step 1: Calculate moles of NiCl2•6H2O

5.00 g • 1 mol

237.7 g = 0.0210 mol

0.0210 mol0.250 L

= 0.0841 M

Step 2: Calculate Molarity

[NiCl2•6 H2O ] = 0.0841 M

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Step 1: Change mL to L.250 mL * 1L/1000mL = 0.250 LStep 2: Calculate.Moles = (0.0500 mol/L) (0.250 L) = 0.0125 molesStep 3: Convert moles to grams.

(0.0125 mol)(90.00 g/mol) = 1.13 g

USING MOLARITYUSING MOLARITY

moles = M•V

What mass of oxalic acid, H2C2O4, is

required to make 250. mL of a 0.0500 Msolution?

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Learning Check

How many grams of NaOH are required to prepare 400. mL of 3.0 M NaOH solution?

1) 12 g2) 48 g3) 300 g