COMMON REACTIONSAcids and bases:
acids: donate proton (H+), form hydronium ion in aqueous solutions, low pH
bases: absorb proton (H+), form hydroxide ion in aqueous solutions, high pH
pH: measures acidity from concentration of hydronium ions, scale from -1 to 14; pH = -log [H3O+]
formed from the reaction between acid
and base; cation from base and anion from acid
Oxidation and Reduction
transfer of electrons from metallic element to non-metallic (closely related to formation of ionic bonds); oxidation – reactant loses one or more electrons to form cation; reduction – reactant gains one or more electrons to form anion: oxidation number; always occur in pairs, oxidizing agent and reducing agent; half reactions – since each reactant behaves differently, must show each half of the reaction separately:
transition elements can have multiple oxidation states depending on what it is paired with; must know the final molecular formula to know its oxidation state
applications: photographic film, free radicals and antioxidants; batteries, anode, cathode;
Reaction rates: molecules collide (often break bonds), concentration, orientation of molecules, kinetic energy of molecules; activation energy, catalyst, exothermic, endothermic
Compare and contrast ionic bonds and covalent bonds. Explain how electronegativity affects bonding and can influence formation of an induced dipole. How is an induced dipole different from a dipole molecule?
Explain the differences between acids and bases. Describe how acidity is measured. What is the product of the reaction between an acid and a base? Is it possible to have a negative pH value? Explain.
Contrast oxidation and reduction. What is an oxidizing agent? a reducing agent? What is an oxidation number? How is it determined? Explain why some elements can have more than one oxidation number.
Be able to determine the molecular formula created by the reaction between a given oxidizing agent and a given reducing agent. Write the half formulas for each element.
Determine the oxidation number of a transition metal given the molecular formula for its product with an oxidizing agent.
Explain activation energy. Contrast endothermic and exothermic reactions.