Types of Mixtures

What’s the difference at the molecular level?

Pure substance, homogeneous or heterogeneous mixture?

• Kool-aid• Fruit loops cereal• Sugar crystals (C6H12O6)

• Air (O2 + N2)• Pizza• Tea• Copper wire (Cu)• Trail mix• Cake batter

Homogeneous Mixture• Uniform composition• One phase (part of sample

with uniform composition/properties)

• Small particles, evenly distributed

• Examples: – Salt water solution– Iodine– Vinegar– stainless steel (mixture of

iron, chromium, and nickel)

Parts of a Solution

• A liquid (solvent) with a substance (the solute) dissolved in it

• Particles are atoms, molecules, or ions (very small)

Heterogeneous Mixture• Not evenly mixed• More than 1 phase• Particles not

uniformly distributed, larger

• Easily separated physically

• Examples: salt and pepper, cereal, rocks, bag of assorted candy

Colloid: A heterogeneous mixture of intermediate-sized particles that don’t settle out

Examples: fog, whipped cream, mayo, smoke

Suspension• A heterogeneous mixture with BIG particles that settle

out when left undisturbed• Liquids that need to be “shaken well before using”

• Examples: oil and vinegar dressing, muddy water