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Solutions

One substance dissolved in another substance

TEKS

10 (A) describe the unique role of water in chemical and biological systems;

10 (B) develop and use general rules regarding solubility through investigations with aqueous solutions;

10 (C) calculate the concentration of solutions in units of molarity; 10 (D) use molarity to calculate the dilutions of solutions; 10 (E) distinguish between types of solutions such as electrolytes

and nonelectrolytes and unsaturated, saturated, and supersaturated solutions;

10 (F) investigate factors that influence solubilities and rates of dissolution such as temperature, agitation, and surface area;

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Solution is...A Homogenous...

Mixture of two or more substances

(evenly mixed)

NaClNaCl HH22OO

It is a physical change …NOTNOT a chemical change

+ Salt WaterSalt Water

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Solution

All solutions consist of two parts:Solute

Solvent

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Solute

The substance being dissolved.

The substance present in the least amount.

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Solvent

The substance doing the dissolving.

The substance present in the highest amount.

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Must a solution be a liquid?

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No…Air is a solutionAir is a solution

Sterling silver is a solutionSterling silver is a solution

It can be gas

It can be solid

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Types of Liquid Solutions

Aqueous A solution with water as

the solventTincture A solution with alcohol as

the solvent.

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Insoluble When a substance cannot be dissolved in a solvent...

Oil Water

++ ==

Therefore, oil is INSOLUBLE in water.

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Solubility A measure of how much a solute can

be dissolved in a solvent under certain conditions

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Limits of Solubility

SupersaturatedSupersaturated …more solute than the solvent can handle.

SaturatedSaturated … the point that no more solute can be added to the solvent or it will be ---

UnsaturatedUnsaturated … more solute can be added to the solvent

What affects the rate of Solubility?

Temperature Agitation Surface Area Pressure (For Gases)

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Solubility GraphsSolubility of KCL

0

10

20

30

40

50

60

0 20 40 60 100

Supersaturated

Unsaturated

saturatedsaturated

Hold all that it can possible hold (at a given

temperature) - concentrated

Contain less solute than it can hold (at a given temperature) - Diluted

More solute then it can hold (at a given temperature)

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Ionization The formation of ions by

the action of a solvent in solution.

NaCl (salt) in to Na+ + Cl-

in waterIons are formed (+ or -)

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Dissociation Is the process of separating ions

during the formation of a solution … the more it dissociates, the stronger it is...

Na+

OH-

Na+

OH-

Na+

OH- Na+

OH-

Strong BaseStrong Base

OH-

NH4+

Weak BaseWeak Base

NaOH Na+ + OH-

OH-

NH4+

NH3NH3

H2O

H2

O

NH3 + H2O NH4+ +

OH-

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Solution Concentration Refers to the amount of solute

dissolved in a solvent. Diluted (less)Concentrated (more)

5 grams5 grams of salt in of salt in 100 grams of Water100 grams of WaterDiluteDilute

VS.VS.

35 grams35 grams of salt in of salt in 100 grams of 100 grams of waterwater

ConcentratedConcentrated

100 g.

100 g.

5 g

35 g

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Electrolytes Because dissolved salts

have positive and negative ions, they are electrolyte solutions, and conduct electricity

NaNa++ClCl--

NaNa++

ClCl--

NaNa++

ClCl--

NaNa++ClCl--

NaNa++

ClCl--

ClCl--NaNa++

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Effervescence

The escape of a gas from a liquid solution

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WaterWater

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Common Solvent

Water is the most common substance on earth

70% of the earth’s surface 65% of your body mass