solution

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presentation in chemistry

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SOLUTION

By: Jazmin April Pescasio

WHAT IS A SOLUTION?

- A homogenous mixture of two or more than two substances

* Homogeneous means that the components of the mixture form a single phase.

- a solute disolved in a solvent (for example a sugar/water solution)

two components of solution:

1) solute is the dissolved substance(the sugar)

2) solvent is the dissolving medium in which the solute is dissolved(the water)

SOLUTE + SOLVENT = SOLUTION

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TYPES OF SOLUTION

gaseous solution

liquid solution

solid solution

GASEOUS SOLUTION

If the solvent is a gas, only gases are dissolved under any given set of conditions. 

Example: air (oxygen and other gases dissolved in

nitrogen).

LIQUID SOLUTION

If the solvent is a liquid, then gases, liquids, and solids can be dissolved.

Examples:Gas in liquid - Oxygen in water.

Liquid in liquid - vinegar in water

Solid in liquid – sugar in water

2 TYPES OF LIQUID SOLUTIONS(Based on how the solutes dissolved in water)

Electrolyte solution- solutes break up into ions in water

Non-electrolyte solution- solutes does not break up into ions

when it is dissolved in water

SOLID SOLUTION

If the solvent is a solid, then gases, liquids, and solids can be dissolved.

Examples:Gas in solid - gases absorbed on Carbon Tablets

Liquid in solid - mercury in gold, forming an amalgam

Solid in solid - All metal alloys, like Brass

When we're talking about how much of the solute is dissolved in the liquid, we're talking about the concentration. 

Four terms to describe the concentration of a solution:

Unsaturated Saturated Supersaturated Dilute

UNSATURATEDThis means that if you were to add more

solute to the liquid, it would keep dissolving.

Example: if you added another teaspoon of salt, it would dissolve, too

SATURATED This means that the liquid has dissolved

all of the solute that is possible. 

Example: If you add one teaspoon of sugar to iced tea, you've got an unsaturated solution.  If you keep adding sugar to iced tea, you eventually get to the point where the rest of the sugar just sinks to the bottom. 

SUPERSATURATED refers to a solution that contains more of

the dissolved material than could be dissolved by the solvent under normal circumstances.

Example:What usually happens in this situation is that the solute starts forming crystals at the bottom of the container. 

DILUTED a solution in which there is a small

amount of solute compared to the total amount of possible solute that can be dissolved in the solvent.

FACTORS AFFECTING RATE OF DISSOLVING

Increased surface area- solid solute in powder form will dissolved faster than when it is compact

Increased agitation- stirring which “forcibly” breaks up the solute particles, allows them to combine faster with the solven particles

Higher temperature

- rate of dissolving becomes faster at higher temperature

SOLUBILITY

Amount of a substance (solute) that dissolves in a unit volume of a liquid substance (solvent) to form a saturated solution under specified conditions of temperature and pressure.

 There are three main factors that control

solubility of a solute.

1) Chemical nature2) Temperature3) Pressure

FACTORS AFFECTING SOLUBILITY

1) CHEMICAL NATURE

 Solubility of a solute in a solvent purely depends on the nature of both solute and solvent. 

   A polar solute dissolved in polar solvent.   Solubility of a non-polar solute in a solvent is large.

   A polar solute has low solubility or insoluble in a non-polar solvent.

2) TEMPERATUREGenerally in many cases solubility increases with the rise in temperature and decreases with the fall of temperature but it is not necessary in all cases. However we must follow two behaviors: 

In endothermic process solubility increases with the increase in temperature and vice versa.   

EX: solubility of potassium nitrate increases with the increase in temperature.  

In exothermic process solubility decrease with the increase in temperature.   

EX: solubility of calcium oxide decreases with the increase in temperature. Gases are more soluble in cold solvent than in hot solvent.

2) PRESSURE

 The effect of pressure is observed only in the case of gases. 

   An increase in pressure increases of solubility of a gas in a liquid.

    EX: carbon dioxide is filled in cold drink bottles (such as coca cola, Pepsi 7up etc.)under pressure.

END OF PRESENTATION

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