Physical ScienceChapter 1 Outline

I. Describing Matter- Matter: Anything that has mass and takes up space. It is the “stuff” that makes

up everything in the universe.A. Properties of Matter

- Examples: Hardness, texture, shape, temperature, flammability, color - Each specific substance has its own combination of properties that can be used

to identify the substance - Chemistry: study of the properties of matter and how matter changes

B. Kinds of Matter1. Elements

- Element: substance that cannot be broken down into any other substances by chemical or physical means

- Elements are called the building blocks of matter because all matter is composed of elements

- Atom: tiny particles-smallest particle of an element- Symbol: one or two letter set of characters used to identify an element

o Example: Aluminum—Al 2. Compounds

- Compound: substance made of two or more elements chemically combined in a specific rationo Example: CO2—Carbon Dioxide—Carbon Atom and Oxygen Atoms

- Formula: combination of symbols that shows the ratio of elements in a compoundo Example: H2O (compound) is different formula than H2O2 (compound)

3. Mixtures- Mixture: made from 2 or more substances

o Elements, compounds, or both—that are together in the same place but are not chemically combined into a new substance

o Example: water is a mixture of Oxygen, salts, and other substances—not found in its pure state

- Mixtures are different from compounds in two ways: Substances in a mixture keep their individual properties

Example: soil is a mixture of sand, clay, water, and other materials

Parts of a mixture are not necessarily present in specific ratiosC. Changes in Matter

1. Physical Change: A change that alters the form or appearance of a material but does not convert the material into new substances- Example: chopping wood, bending wire into shapes, changes in state- Matter has 3 principle states: Solids, liquids, and gasses

2. Chemical Change- Chemical Change (Chemical Reaction): change in matter that produces

new substances o Example: rusting of iron and burning of gasoline in a caro Physical changes and chemical changes are the two basic ways that

matter can change

II. Measuring MatterA. Mass

1. Weight and Mass- Weight: measure of the force of gravity on you- Example: scientists rely on property that is constant wherever you are—

Mass - Mass: measurements of how much matter it contains - Unlike weight, an objects mass will not change if the force of gravity on it

changes 2. Units of Mass

- International System of Units (SI): System of measurement based on multiples of ten and on established measures of mass, length, and time

- Mass-kg- Gram-g

B. Volume- Volume: amount of space that matter occupies - For rectangular objects: Volume=cm x cm x cm= cm3

- Cm3 reads as cubic centimeters- Other measurements to measure liquids—liter (L) and milliliter (mL)

C. Density- Density: measurement of how much mass is contained in a given volume- Density=Mass/Volume - g/cm3—grams per cubic centimeter

III. Particles of MatterA. Early Ideas About Atoms

- Today, scientists use the word atom for the smallest particle of an element B. Dalton’s Ideas About Atoms

- John Dalton- Atom Characteristics

o Atoms cannot be broken into smaller pieces. Dalton imagined atoms to be like tiny marbles or rigid spheres that are impossible to break

o In any element, all the atoms are exactly alikeo Atoms of different elements are different o Atoms of 2 or more elements can combine to form compoundso Atoms of each element have unique mass

o The masses of the elements Ina compound are always in a constant ratioC. Ideas About Atoms TodayD. Atoms and Molecules

- Chemical Bond: the force that holds 2 or more atoms- Molecule: combination of 2 or more atoms that are bonded together

o Example: O2 and H2OE. The Atom as a Model

IV. Elements from EarthA. Gold and DensityB. Copper and Electrolysis

- Electrolysis: process by which an electric current breaks chemical bonds (“electric cutting”)

- Electrodes: a metal strip that gains or loses electrons during electrolysis C. Iron and the Black Furnace