USC Bridge 1.2 molecules, compounds, and mixtures
Molecules
Two or more atoms bonded together i.e.: H2
Compound
Molecule with two or more different kinds of atoms bonded together i.e.: C6H12O6
can be separated only by breaking bonds
are all homogeneous or the same
Mixtures
Two or more components physically intermixed 3 types: solutions, colloid, suspension
no chemical bonding between components
can be separated by straining or filtering
heterogenous or homogeneous
Solutions
Homogeneous mixtures of components that may be gasses, liquids, or solids.
Solute particles are very tiny, do not settle out or scatter light
Concentration of solutions
Weight/volume mg/dl
percent or parts per 100 parts
molarity or moles/liter- most precise way of describing a concentration of a solution
Solvent
Present in the greatest amount
Solutes
Substance present in the smallest amount
Molecular weight
A mole of any element or compound is equal to its atomic weight
Avogadros number
One mole of any substance always contains exactly the same number of solute particles
Colloids
Also called emulsion, are heterogeneous mixtures which means that their composition is dissimilar in different areas of the mixture.
Solute particles are larger than in a solution and scatter light; do not settle out
colloids can change from liquid to gel
Suspension
Heterogeneous mixture
visible solutes that tend to settle out
solute particles are very large, often visible, settle out and may scatter light
When two atoms of two different elements bind together they form an:
Compound
What mixtures are homogeneous?
Solutions