Properties of Metals and Nonmetals (Section)
Write balanced equations for the following reactions: (a) potassium oxide with water, (b) diphosphorus trioxide with water, (c) chromium(III) oxide with dilute hydrochloric acid, (d) selenium dioxide with aqueous potassium hydroxide.
Week 2 (no class week oneProfessor illness) Geology 207 Environmental Geology, Geochemical Cycles Dr. Klaus Neumann INTRODUCTION / REFRESHER CHEMISTRY Atom Basic building block. Proton (+) Mass =1 Neutron (-) Mass = 0 Electron (0) Mass = 1 Atomic Number = Number of protons Determine number of neutron (Atomic mass – atomic number) Balance charge using protons and electrons (neutron charge = 0) - Most stable (rarely react) when out most electron orbit is completely filled. (Noble Gases- He, Ne, Ar, Kr, Xe, Rn) Ion has a charge (+ or -) Cation Positive charge (+) Anion Negative charge (-) Compounds – atoms together NaCl – Ionic compound Covalent – (NH3) - Metallic Bonds – Metal – Conductor (electricity) – Hydrogen Bonds – Isotope – Change in neutrons Radioactivity –most reactive Carbon-14 (most radioactive, choosing from carbon-12, carbon-13, & carbon-14) Mole atomic mass (grams) or molar ratios (Avogadro’s number) CHEMICAL REACTIONS 1. Precipitation/Dissolution 2. Acid/Base 3. Oxidation Reduction Precipitation/Dissolution Reactant (left side) Products (right side) Na(+) + Cl(-) NaCl Acid / Base (Sum always remains the same) HCl H(+) + Cl(-) Acid H20 H(+) + OH(-) Acid NaOH Na(+) + OH(-) Base pH – level of acidity; Oxidation / Reduction Oxidation is the loss of electrons or an increase in oxidation state by a molecule, atom, or ion. Reduction is the gain of electrons or a decrease in oxidation state by a molecule, atom, or ion. CH4 + 2O2 CO2 + 2H2O Carbon changes charge WATER (Covalent) Vapor Liquid Solid Density is temperature dependent. If you heat water it will take more space FRESHWATER