Week 1 (gps)

Chemistry: science of the structure, composition and properties of matter

Matter + Energy

Mind Map: Matter

Central Idea: Matter

• Definition: Anything w. mass + volume

Main Branches:

1. Classification of Matter

   • Pure Substances: any matter that is HOMOGENEOUS and has a fixed composition by mass

     • Elements: contain atoms of a SINGLE type and CANNOT decompose further

     • Compounds: 1+ type of element; compositions are FIXED

   • Mixtures: 2+ diff substances mixed together

     • Homogeneous Mixtures: UNIFORM combo of substances at a molecular level AKA components are EVENLY mixed and visually indistinguishable.

       • Ex: saltwater (NaCl + H2O)

     • Heterogeneous Mixtures: NOT uniformly dispersed AKA scattered

1. Physical Properties: measured w/o changing the identity + composition of a substance

   • Ex: color, odor, density, melting/boiling point, solubility, texture

2. Chemical Properties: lead to changes in the identity + composition of a substance

3. Changes in Matter

   • Physical Changes/Rxn: changes that accompany the measurement of PHYSICAL properties

     • Reversible Changes

     • Irreversible Changes

       • Ex: phase changes

   • Chemical Changes/Rxn: changes that accompany the measurement of CHEMICAL properties

     • Formation of New Substances

     • Energy Changes

4. Atomic Structure

   • Atoms

     • Protons (+)

       • the identity of an element is determined by the atomic #/proton #

     • Neutrons (0)]

       • neutron # does NOT change an elements identity

       • neutrons add MASS to an atom

     ISOTOPE: element w same # of protons but diff # of neutrons AKA change in neutron #

     • Electrons (-)

   • Elements

     • Atomic Number

       • atomic # = proton # = electron #

       • periodic table is organized by INCREASING atomic #

     • Atomic Mass

       • proton # = atomic # = electron #

       • atomic mass = p - n (proton # - neutron #)

   • Molecules: smallest identifiable sample of a substance

     • Monatomic Molecules: isolated atoms (do not want to interact and react w other atoms) AKA noble gases (g18)

       • He, Ne, Ar, Kr, Xe, Rn

     • Polyatomic Molecules: 2+ atoms linked (too much)

       • O3, P4, S8, C60

     • Diatomic Molecules: EXACTLY 2 atoms (paired with itself!!)

       • 7 up aka. H2, O2, N2, F2, Cl2, Br2, I2

     • Chemical Formulas

     • Bonding Types

5. Energy and Matter

   • Forms of Energy:

     • Heat (q)

       • endothermic: absorb/input heat

       • exothermic: release heat

     • Chemical

     • Electrical

     • Light

     • Nuclear

     • Mechanical Energy

       • Kinetic: energy associated w motion

       • Potential: energy associated w. position

     • Conservation of Energy: Energy CANNOT be created or destroyed. It can ONLY change from one form to another.

6. Laws and Theories

   • Law of Conservation of Mass

   • Law of Definite Proportions

   • Atomic Theory of Matter

Sub-Branches:

• Elements

  • Metals

  • Non-metals

  • Metalloids

• Compounds

  • Chemical Formulas

  • Chemical Reactions

• Homogeneous Mixtures

  • Solutions

  • Alloys

• Heterogeneous Mixtures

  • Suspensions

  • Colloids

• Solid

  • Crystalline Solids

  • Amorphous Solids

• Liquid

  • Viscosity

  • Surface Tension

• Gas

  • Pressure

  • Boyle's Law

• Reversible Changes

  • Melting

  • Freezing

• Irreversible Changes

  • Burning

  • Decomposition

• Formation of New Substances

  • Combustion

  • Oxidation

• Energy Changes

  • Exothermic Reactions

  • Endothermic Reactions