What is chemistry The study of matter and how it changes Example of chemistry: soap food, glass Because of what it is made of or how it changes

What is matter? Anything that has mass and occupies space

BASIC MATTER can be broken down into… ATOM: SMALLEST PARTICLE THAT HAS PROPERTIES OF AN ELEMENT ELEMENT: SUBSTANCE THAT CANNOT BE BROKEN DOWN INTO A SIMPLER SUBSTANCE 3. COMPOUND: SUBSTANCE MADE OF ATOMS OF MORE THAN 1 ELEMENT BOUND TOGETHER

HOW ARE ELEMENTS AND COMPOUNDS WRITTEN? USING A FORMULA this representation uses chemical symbols and numbers that tell the number of atoms contained in the basic unit of the substance element: N compound: H2O

What is the smallest unit of a substance that exhibits all of the properties characteristic of that substance? Molecule

Examples of formulas C16H10N2O2= indigo 16 +10+2+2= 30 atoms C8H10N4O2 = caffeine 8+10+4+2 = 24 atoms C3H8O = rubbing alcohol 3 +8+1 = 12 atoms

What is the difference between a pure substance and a mixture? matter with a fixed composition and definite properties, can’t be separated or broken down by physical actions such as boiling grinding or melting represented by a chemical formula C6H12 O6 Mixture: a combination of more than one pure substance air, grape juice

Matter and Energy What is the kinetic theory? All matter is made of atoms and molecules that act like tiny particles Tiny particles are always in motion the higher the temperature, the faster the particles move 3. At the same temperatures, the more massive particles move slower than the less massive particles

What are the common states of matter? Solid: fixed position, rigid, can vibrate, closely packed 2. liquid: closely packed but can slide past each other gas: constant state of motion, rarely stick together 4. plasma: fast moving charged particles

Solid: fixed position, rigid, can vibrate, closely packed 2. liquid: closely packed but can slide past each other gas: constant state of motion, rarely stick together 4. plasma: fast moving charged particles

What is energy? Ability to change or move matter What does changing states of matter do to a substance? changes attractive forces between molecules, doesn’t change composition of a substance

State the law of conservation of mass? Mass can not be created or destroyed State the law of conservation of energy? Energy can not be created or destroyed.

Changes of states of matter sublimation LIQUID Boiling or evaporation GAS Solid melting condensation freezing

What is a chemical property of a substance? The way a substance reacts with others to form new substances with different properties by either combining with other elements or by breaking apart into new substances (corrosive, reactive,flammable) ex mercury…toxic steel…… reactive with oxyen to form rust sodium …. Flammable in O2

What is reactivity? Ability of a substance to combine chemically with another What is flammability? Chemical property that describes whether substances will react in the presence of O2 and burn when exposed to flame

What are physical properties? Characteristics of a substance that can be observed or measured without changing the composition of the substance Remain constant for specific pure substances Shape, color, odor, texture, melting point, boiling point, strength, hardness, ability to conduct electricity or heat, magnetism, density Ex mercury is liquid at room temperature

How to classify mixtures? By how thoroughly the substances mix together. Mix solid + liquid…. Homogeneous mixture clear and mixing occurs between the individual units and is the same throughout salt + water= salt water Heterogeneous cloudy mixture and mixture between substances isn’t uniformly mixed flour + water

Liquid + liquid Miscible Describes two or more liquids that are able to dissolve into each other in various proportions gasoline Immiscible Describes two or more liquid that do not mix into each other. oil and water

DENSITY: physical property D= m/V density equals mass divided volume Buoyancy: the force with which a more dense fluid pushes a less dense substance upward

What is a chemical change? A change that happens when a substance changes composition by forming one or more new substances cellular respiration photosynthesis combustion clues: energy released, smell or smoke

What is a physical change? A change in the physical form or properties of a substance that occurs without a change in composition Ex: melting, freezing, evaporating, grinding, dissolving,

Inquiry lab pg 57 Volume of H2O Mass of cylinder + H 2O 10 20 30 40 50 10 20 30 40 50 60 70 80 90 100