matter - mrs. hurd's science...
TRANSCRIPT
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