CHAPTER 3 MATTER. Noyes Noyes Uniform ? Separated by physical means? yesNo Broken chemically?

CHAPTER 3

MATTER

No yes No yesUniform?

Separated by physical means?

yes No

Broken chemically?

HETEROGENEOUS MIXTURE Made up of more than one thing, not

uniform throughout Two or more particles sitting next to

each other Each piece retains its own properties Not chemically bonded Ex. Pizza; granite; sand/water

HOMOGENEOUS MIXTURE

A Solution Made up of two or more particles not

chemically bonded together but uniform throughout

True solutions cannot be filtered Ex. Air, salt water, brass, CuSO4 (aq)

Steve Spangler- Oobleck on Ellen

TYPES OF SOLUTION SYSTEMS GAS – GAS…………………….air GAS – LIQUID…………………soda LIQUID – GAS…………………humid air LIQUID – LIQUID………………vinegar SOLID – LIQUID……………….Kool-aid SOLID-SOLID………………….alloys

(brass) GAS –SOLID………..pop rocks

Parts of a Solution

SOLUTE = the dissolved material (sugar)

SOLVENT = the dissolving material (usually water)

MOLARITY = way of measuring the concentration of a solution; the ratio between solute and solvent

SEPARATING A MIXTURE

Filtration Magnet Picking out pieces Crystallization/Evaporation Chromatography Distillation- separate by boiling point

Distillation

Separation of Mixtures Movie

(mixtures and compounds)

PURE SUBSTANCE

A homogenous material that is made of only one kind of particle that is uniform throughout

1. Element= substance composed of 1 kind of atom (smallest particle) –Cannot be broken down into simpler

substances–91 Naturally occurring elements–Dmitri Mendeleev developed 1st

widely used periodic table

2. Compound= a substance composed of more than one type of atom chemically bonded together–Properties of the compound are

different than the elements putting it together

–MOLECULE= smallest particle of a compound (2 or more atoms)

COMPOUND VS. MIXTURE

Made of one kind of particle (molecule) Molecules are chemically bonded Properties diff. than the elements Need a chem. rxn to separate Specific ratios (formula)

Made of 2 or more particles Particles are physically sitting next to each other Properties of mixture similar to components Separate by physical means Ratio not important

Change Video

PHYSICAL PROPERTIES Characteristics that can be observed w/out

altering the identity of a material Describes the substance by itself

INTENSIVE PHYSICAL PROPERTY = a property not dependent on the amount of matter presentExamples: density, temperature, color,

conductivity, crystal shape, melting/boiling point, ductility(draw into wire), malleability (shape or pound)

EXTENSIVE PHYSICAL PROPERTY = a property that is dependent on the amount or how much of the matter is present

Examples: length, width, mass, volume, heat

PHYSICAL CHANGES

Substance remains the same after the change

Change in property without change in identity

Examples: cutting, crushing, change in state (evaporation, freeze, melt, etc.), dissolving, crystallizing, heating/cooling, grinding, pounding

CHEMICAL PROPERTIES

Properties that can be observed only when substances interact with each other

Describes how something acts when another substance is around

Alters identity in a chemical reaction Examples: ability of iron to rust, ability

of wood to burn, reacts w/acid

CHEMICAL CHANGE

Change one substance into a new substance with new properties

Clues to a chemical change: Change in color Change in temperature Gives off gas Gives off light Change in odor Forms a precipitate (solid particles)

STATES OF MATTER

SOLID- definite shape and volume; particles are tightly packed and moving slowly

LIQUID- flows, definite volume, assumes shape of container, particles slide past each other

GAS- flows, assumes shape and volume of container, moves rapidly, freely

LAW OF CONSERVATION OF MASS Matter cannot be created nor destroyed Mass reactants = mass products

2H2 + O2 2H2O

10.0 g 79.4g ?g

89.4 g

LAW OF DEFINITE PROPORTIONS Joseph Proust Stated that regardless of the amount, a

compound is always composed of the same elements in the same proportion by mass

Water is always 2:1 ratio

Percent by mass or % composition = mass of element

mass of compound X 100Example Sucrose (sugar) 20 g sample

C 8.4 g 8.4/20 x 100 = 42% C

H 1.3 g 1.3/20 x 100 = 6.5% H

O 10.3 g 10.3/20 x 100 = 51.5% O

LAW OF MULTIPLE PROPORTIONS John Dalton Found that compounds composed of

same elements can occur in different ratios

Relates the composition of 2 compounds composed of same element Example: H2O H2O2

CuCl2 CuCl

(Law of M.P. cont.)

States: that when different compounds are formed by combination of the same elements, different masses of one element combine with the same relative mass of the other element in a ratio of small whole numbers

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