Solute and Solvent

Mixtures and Solutions

Heterogeneous materials - can see two parts

Matter

Homogeneous materials can see only one

thing - one set of properties

Homogeneous mixtures

They’re mixed together so well you only see one thing – it looks pure

but it isn’t

Pure substancesYou can only see one thing because there is only one kind of particle in

it.

Mechanical Mixture

Solution

Review Solutions

Are solutions homogeneous or heterogeneous? Homogeneous

Are solutions mixtures or pure substances? Mixtures

What kind of states can a solution be? Solid, liquid, or gas

What are the two “s” words that every solution must have? A solute and a solvent

In a salt water solution…

Is salt the solute or the solvent? Solute

Is water the solute or the solvent? Solvent

What does the solute do? Gets dissolved

What does the solvent do? Does the dissolving

Solute (salt)

Solvent (water)

A Salt Water Solution

Factors Affecting How Fast a Solute Dissolves

1. Temperature

2. Stirring or Shaking

3. Crushing (Surface Area)

4. Pressure

1. Temperature If we heat particles they will move faster

• The solvent will carry the solute particles away faster

So…

Hotter = Dissolve Faster

2. Stirring or Shaking

Stirring or shaking a solution moves the solute particles around so that they are closer to water particles

• the water particles can then attract them easily and carry them away!

So…

Stir or Shake = Dissolve Faster

3. Crushing (Surface Area)

When a sugar cube is broken into small pieces, the individual sugar particles can get closer to water particles

• the water particles can then attract them easily and carry them away!

Dissolving happens on the surface of particles

• When solute is broken up, there is more surface area where dissolving can occur

broken up

4. Pressure

Pressure forces gas particles into the spaces between the liquid particles

Pressure is used to dissolve carbon dioxide gas in liquid pop

gas

So…

More pressure = Dissolve Faster

Exteme Example of Pressure

Altitude Sickness and Nitrogen Narcosis (“The Bends”)