Matter

Matter

Anything that has mass and takes up space (volume)

Mass ● Mass is the amount of matter in an object

○ Same no matter where in the universe ● Mass vs. Weight

○ Weight is a measure of the gravitational force on an object ○ Weight can change depending on location in universe

Volume ● The amount of space taken up by an

object ● Measuring Volume

○ Liquids - graduated cylinder ■ Use the meniscus

○ Regular Solids - Length x width x height

○ Irregular solids - graduated cylinder ■ Displacement of water

Density

● How much matter is in a certain amount of space

Calculating Density

● Density = mass/volume ● Units for density: g/cm3 or g/mL

● Frank has a paper clip. It has a mass of 9g and a volume of 3cm3. What is its density?

● Frank also has an eraser. It has a mass of 3g, and a volume of 1cm3. What is its density?

● Which is more dense?

States of Matter

● The physical state of matter can change ● Solid ● Liquid ● Gas

Solid

● Molecules very close together and cannot move around -- move back and forth in place

● Has definite shape and definite volume

Liquid ● Molecules are close together

and slowly move past each other

● Has NO definite shape but has a definite volume

● Takes shape of container

Gas

● Molecules far apart and move freely at high speeds

● Has NO definite shape and NO definite volume

Freezing Point

● The temp at which a liquid changes into a solid

Boiling Point

● Point at which a liquid changes into a gas

● Boiling Point of Water = 100 degrees Celsius

Melting Point

● Temp at which a solid becomes a liquid

● Melting point of water is 0 degrees Celsius

Changes of state

● Condensation - phase change from gas to liquid

● Sublimation - phase change from solid to gas

● Evaporation - phase change from liquid to gas

Solution = solvent + solute

● Solvent = substance in which another substance is being dissolved into

● Solute = substance being dissolved

● Solubility - ability of the solute to be dissolved

Physical Properties and Changes

● Physical Properties ○ Characteristic observed

WITHOUT changing the substance

○ Examples: ■ Color ■ Odor■ Taste ■ Temp ■ Density ■ Boiling point

Physical Changes

● Change that affects physical properties such as size and shape

● Examples:○ Freezing/melting○ Solubility ○ Cutting ○ Crushing

Chemical Properties and Changes

● Chemical Properties ○ Ability to go through

chemical change ○ Examples:

■ pH■ Reactivity ■ Concentration ■ Chemical composition

Chemical Changes

● Change that turns substance into something else

● Examples:○ Flammability ○ Rusting ○ Cooking ○ Malleability

Clues to Chemical changes

● Color changes ● Heat change ● Fizzing ● Foaming ● Odor

Chemical changes -- change the substance into something else.

Elements, Compounds, and Molecules

Elements

● Pure substance that cannot be separated into a simpler substance

Molecule

● A substance made of two or more elements chemically bonded in a set ratio

● Examples:○ Water - H

2O

○ Salt - NaCl

Mixtures

● Combo of two or more pure substances that are not

chemically combined

● Held together by physical forces

● Each item retains its properties in the mix

Mixtures

Heterogeneous - substances NOT evenly distributed

Homogeneous - substances are evenly distributed