Solutions Mixtures

 Mixture – a substance made by mixing two or more substances together

 Heterogeneous mixture – not uniform appearance and composition throughout  You can see and separate the different components of the mixture  Cheerios in milk  Salad

 Homogeneous mixture – uniform appearance and composition throughout  Looks the same  Salt in water  Kool-aid Solution

A solution is a homogeneous mixture It looks the same throughout!  An aqueous solution is water that contains dissolved substances Solvents & Solutes

 Solvent – the dissolving medium. This is doing the dissolving! Usually in greater quantity.

 Solute – the dissolved particles. They are being dissolved! Usually in smaller quantity. Solvents & Solutes

A solvent dissolves the solute.

The solute becomes dispersed in the solvent. Solvation

Solvation - Individual solute ions break away from the solid and become surrounded by solvent molecules. Also called dissociation for ionic compounds Solvation Solvents & Solutes

Solvents and solutes may be solids, liquids or gases!

Sugar in water: Solid in liquid Carbonated water: Gas in liquid Steel: Solid in solid Solvents & Solutes

If you have hard water, what is the solvent? The solute? Hard water is water that has dissolved ions of heavy metals such as lead, iron and copper within it. The water is the solvent. The ions (metals) are the solute.

If you have an aqueous solution of magnesium chloride

(MgCl2 (aq) ). What is the solvent? The solute? The water is the solvent. Magnesium chloride is the solute. Universal Solvent

Water is known as the UNIVERSAL SOLVENT because it can dissolve more substances than any other liquid! Soluble & Insoluble

Soluble – solute that can be dissolved in a solvent Salt in water

Insoluble – solute that cannot be dissolved in a solvent Aspirin in water Miscible & Immiscible

Miscible – Two liquids that do mix together Water and alcohol

Immiscible – Two liquids that do not mix with each other Water and oil Polar & Nonpolar

 Like dissolves like!!

 Polar solvents dissolve polar solutes

 Nonpolar solvents dissolve nonpolar solutes Electrolytes and Nonelectrolytes

 Electrolyte - compound that conducts electricity when in an aqueous solution  All ionic compounds are electrolytes because they dissociate into ions.  Strong electrolyte - all the dissolved solute exists as ions.  Conducts electricity strongly  The ions dissociate!  Weak electrolyte - some of the solute exists as ions.  Conducts electricity poorly  Nonelectrolyte – compound that does not conduct electricity in either aqueous solution or the molten state.