chemistry joke what do you call iron blowing in the wind? febreeze!
TRANSCRIPT
Chemistry Joke
What do you call iron blowing in the wind?
Febreeze!
“Matter and
Change”
ChemistryChemistry - the study of matter and its changes
• Matter - anything that has mass and takes up space – Air and smoke are examples of matter– Light and heat are energy, not matter
• Mass - quantity of matter (numbers of atoms or molecules)
• Weight - measure of gravitational attraction– Dependent on gravity of location
StudyStudy of Matter of Matter
• States of Matter
• Classifications of Matter
• Physical Properties of Matter
• Physical Changes of Matter
• Chemical Properties of Matter
• Chemical Changes of Matter
StatesStates of Matter
• Gas - indefinite volume and shape• Liquid - definite volume, indefinite shape• Solid - definite volume and shape• Plasma – a gas that has a charge because it has
been heated and has lost its electrons.
Classifications of Matter
plasma
Pure Substances• Elements
– Simplest form of matter / building blocks – Composed of only one type of atom– Cannot be simplified– Ex: Any element on periodic table
• Compounds – Substances that can be separated only by chemical
means into simpler substances– Can be written as a chemical formula– Ex: water, H2O; baking soda, NaHCO3; ammonia,
NH3
MixturesMixtures• 2 Types
– Homogeneous• Composed of only one phase of matter • Completely uniform throughout• Also called a solution• Ex: salt water, air
– Heterogeneous • Non-uniform distribution • Ex: apple, salad
• Can be separated by physical means– Filtration, distillation, chromatography
Physical Separation of a
Homogeneous Mixture by Distillation
alcohol and water
alcohol
liquid
Physical Separation of a Heterogeneous Mixture Using Magnetism
Physical Separation of a Homogeneous Mixture Using Chromatography
Physical PropertiesPhysical Properties of MatterProperties that can be observed and measured without changing the composition of the substance
Color SolubilityElectrical Conductivity
State of Matter (solid, liquid, gas)
DensityThermal Conductivity
Melting and Boiling point
Metallic Characteristics(malleability, ductility, & luster)
Magnetic Properties
Physical Changes Physical Changes of Matterof MatterChanges in Form not SubstanceChanges in Form not Substance
• Phase changes are physical!!– Melting, freezing, boiling, condensing,
evaporating• Tearing, breaking, cutting, crushing• Dissolving is a physical change!!
Chemical PropertiesChemical Properties of Matter
• Ability of a substance to undergo a chemical reaction and form a new substance
• Flammability / Combustibility• Acidic or basic• Reactivity
Chemical Changes Chemical Changes of Matterof MatterIndicators that a chemical change may
have happened: Energy is absorbed or released
(temperature changes) Color changes Gas is produced (bubbling, fizzing, or odor
change; smoke) Precipitate is formed - a solid that
separates from solution (won’t dissolve) Irreversibility - not easily undone
Words Associated Words Associated with Chemical Changewith Chemical Change
Burn Decompose Corrode
Rot Ferment Cook
Rust Explode -----------
Chemical Reactions Chemical Reactions of Matterof Matter
Starting substances called reactants change to form products.
Reactant + Reactant → Product
The Law of Conservation of MassThe Law of Conservation of Mass(of Matter!)(of Matter!)
• In any physical or chemical change, mass is neither created nor destroyed; it is CONSERVED!
• In other words, the mass of the reactants will ALWAYS equal the mass of the products.
reactants → product
43.43 g Original mass = 43.43 g Final mass
Chemistry Joke
Q: H2O is water and H2O2 is hydrogen peroxide. What is H2O4?
A: Drinking, Bathing, Etc.!