Matter

Matter anything that has mass and takes up space states of matter solid - definite shape and volume liquid - definite volume, no definite shape gas - no definite shape or volume plasma – photons moving at high velocity (sun, fluorescent lights)

Law of Conservation of Matter matter is neither created nor destroyed in any chemical process Matter can just change form Law of Conservation of Mass Because matter is not created nor destroyed, the mass of the reactants is equal to the mass of the products

Types of Matter

Substance Pure form of matter, can not be physically separated. Two types: Elements– a pure substance made up of only one kind of atom Periodic Table of the Elements: carbon, nitrogen Compound – two or more elements chemically bonded sodium chloride (NaCl) magnesium oxide (MgO)

Mixture- A blend of two or more pure substances Not chemically combined Can be separated Heterogeneous mixture – a mix with visibly different parts granite chocolate chip cookies Homogeneous mixture – does not contain visibly different parts ( looks same throughout) Kool Aid Seawater Air-

Properties of Matter Physical properties Chemical properties density color melting point boiling point Chemical properties Flammability/ combustibility Reactivity

Physical Changes Does NOT alter the identity of the substance. Can affect the size, shape or state of matter but not the composition. Ex: Ice  water  steam Changes state but not composition- H2O A good indicator of a physical change is if it is reversible

Other Examples of Physical Changes Cutting Crushing ***Dissolving ***

Chemical Changes Does alter the identity of the substance A new substance (s) is made with different properties Ex: Na + Cl NaCl Sodium (grey highly reactive metal) + chlorine (a poisonous green gas) produces sodium chloride (table salt)

Indicators of a Chemical Change

1. Energy Change Fire, heat, electricity, light, or a temperature change (gets hot or cold)

2. Produces a Precipitate~ a solid formed from 2 liquids

3. Releases a Gas Ex: Bubbles or fizzing

4. Color Change

Separating Mixtures

1. Filtration- separates by particle size.

2. Chromatography- separates by molecular size 2. Chromatography- separates by molecular size. The smaller, lighter molecules travel the farthest up the paper

3. Magnetism

4. Distillation- uses the different boiling points of compounds

5. Density: Decanting/ Centrifuging- More dense liquid/solid on bottom less dense on top

6. Crystallization via Evaporation

Separating Compounds there is only one technique used to separate compounds and that is…

7. Electrolysis- separates a compound by running an electrical current through it.

Changes in State of Matter

Changes in State a physical change of a substance from one state of matter to another ALWAYS involves a change in energy

Endothermic Phase Change Absorbs energy solid  liquid (Melting) liquid  gas (Vaporization aka Boiling) Molecules must overcome the attractive forces holding them in the more condensed state

Exothermic Phase changes Releases Energy Molecules go from a higher energy state to a lower energy state gas  liquid (Condensation) liquid  solid (Freezing)

Evaporation Form of vaporization that occurs on the surface of a liquid. Some liquids evaporate more quickly due to lower boiling point Ex: Water versus Rubbing Alcohol Volatile liquids