Matter Chapter 2.1
Matter Anything that has mass and occupies space. Chemistry is the study of matter and how it changes.
PLEASE KEEP YOUR HANDS IN THE BOAT AND PLEASE DON T FEED THE ANIMALS.
Pure Substances Uniform and definite composition Can t t be separated physically only chemically 22 types Elements & compounds
Pure Substance ElementsElements a substance that cannot be broken down into smaller substances. AtomsAtoms smallest particle that has properties of an element. Both Both expressed by symbols
Compounds Compounds a substance formed when two or more elements chemically combine together.
Molecules The smallest unit of a substance that exhibits all of the properties characteristic of that substance. Two Two or more atoms chemically combined
Chemical Formulas Ex. C 16 H 10 N 2 O 2
Mixtures A physical combination of more than one substance. (Two Types)
Homogeneous Mixtures Solutions Same throughout (miscible) ex: flat soda, salt water, carbonated drinks
Heterogeneous Mixtures Not uniformly mixed (immiscible) Substances that need to be shaken ex: noodle soup, granite
Classifying Liquid Mixtures: miscible-dissolve into each other immiscible-don t mix into each other. You can see layers ex: oil and water.
Matter and Energy 2.2
Kinetic Theory 1.All matter is made of atoms and molecules that act like tiny particles.
Kinetic Theory 2.These tiny particles are always in motion. The higher the temperature, the faster the particles move.
Kinetic Theory 3. At the same temperature, heavier particles move slower than lighter particles.
Phases/States of Matter Gas liquid solid plasma
States of Matter - Gases no definite shape. no definite volume. easy to compress. most random arrangement of particles. Most spread out.
Gases Property of gases is called pressure. the force exerted per unit area of a surface
Liquids Definite volume no definite shape (takes shape of container) Difficult to compress disorderly arrangement on particles Close together
Liquids Property of Liquids is called viscosity. the resistance of a fluid to flow
Solids Definite shape Definite volume Difficult to compress Orderly arrangement of particles close together Smallest amount of movement of particles.
Energy The ability to change state or move matter. Changing state does not change composition of the substance
Changes of State solid liquid gas
Law of conservation of matter Matter cannot be created or destroyed. It only changes its state or rearranges its atoms.
Law of conservation of energy Energy cannot be created or destroyed. It converts from one form to another during chemical or physical changes.
Properties of Matter 2.3
Physical Property A characteristic of a substance that can be observed or measured without changing the composition of the substance.
Physical Property Melting and freezing points. Solubility Dissolving of a solid into a liquid. Density
Density mass/volume (D=m/V) UNITS: mass (g) Volume (ml) or (cm 3 ) density (g/ml) or (g/cm 3 )
Density Buoyancy- The force with which a more dense fluid pushes a less dense substance upward. ex. floating ice.
Chemical Properties The way a substance reacts with others to form new substances with different properties.
Chemical Properties Flamability Reactivity corrosion
Physical Changes A change in the physical form or properties of a substance that occurs without a change in composition.
Chemical Change A change that occurs when a substance changes composition by forming one or more new substances.
Chemical Change 4 signs: Evolution heat or light Color change Formation of gas Formation of a precipitate (solid residue)