composition & organization of matter

• matter - occupies space and has mass
• matter is made up of tiny particles such as atom, molecules, & ions
• there are three states of matter: solid, liquid and gas.
• solid is a matter with a definite shape and volume
• there are two types of solid: crystalline and amorphous
• • crystalline solid a solid that has a regular structure and is made up of repeating units of atoms
• amorphous solid a solid that does not have a regular structure and is not made up of repeating units of atoms
• liquid - a matter that has definite volume but no definite shape
• particles in liquids move slower than those in gases but faster than those in solids
• Gas is a matter that does not have a definite shape or volume
• The air you breathe is a mixture of gases such as nitrogen, oxygen, and water vapor. 
• atom - is the smallest unit of matter. it combines to form molecules
• matter is classified into mixtures and pure substance
• An atom consists of the nucleus at the center.
• nucleus is the combination of protons and neutrons.
• Electron, proton and neutrons are the sub-atomic particles of an atom 
• An element is a pure substance formed with atoms that contains the same number of proton
• Element is the basic form of matter which cannot be broken down into simpler particles
• molecule - When two or more atoms combine
• Molecules are classified into the following: 

  Monoatomic molecules: Helium (He), Neon (Ne) 

  Diatomic molecule: Hydrogen (H2), Oxygen (O2), Fluorine(F2). 

  Triatomic molecule: Ozone(O3). 

  Polyatomic molecule: Phosphorous(P4), Sulphur (S8) 
• compound - composed of two or more elements. 
• Homogeneous mixtures are also called solutions
•  If all portions of a material are in the same state, have no visible boundaries, and are uniform throughout, then the material is homogeneous.
• If the composition of a material is not completely uniform, then it is heterogeneous
• The components of heterogeneous mixtures can usually be separated by simple means.
• element - A substance that cannot be broken down into chemically simpler components
• compound -  substance that can be broken down into chemically simpler components
• A homogeneous mixture, also called a solution, is a mixture in which the composition is uniform throughout the mixture
•  heterogeneous mixture is a mixture in which the composition is not uniform throughout the mixture.
• solution - is a mixture of two or more substances
• solutions are homogenous mixtures
• a solution has two parts: solute & solvent
• SOLUTE - the substance who dissolves
• SOLVENT - A liquid that can dissolve a substance.( or the one who does the dissolving)