Acids and bases are used throughout chemistry.
                        Definitions of acids and bases
                          There are three common definitions of acids and bases:
                        
                          
                            - Arrhenius acid: Produces hydronium ion in  water.
 
                            - Arrhenius base: Produces hydroxide ion in  water.
 
                            - Brønsted-Lowry acid: Donates a proton (H+1)
 
                            - Brønsted-Lowry base: Accepts a proton
 
                            - Lewis acid: Accepts electrons
 
                            - Lewis base: Donates electrons
 
                          
                         
                        Strong acids and bases are ones in which most molecules  perform their “duty” while weak acids and bases only have a few acid and base  molecules that act as acids and bases.   There are only a few strong acids and bases to remember—the rest will  most likely be weak.  Strong acids: HCl, HBr, HI,  HNO3, HClO3, HClO4.  Strong bases: NaOH, KOH, Ca(OH)2,  Ba(OH)2, Sr(OH)2
                        A conjugate acid is what remains after a base does its  “job”.  A conjugate base is what’s left  after an acid does it’s “job.”  Strong  acids or bases form a weak conjugate and vice versa.
                        Equilibrium of acids and bases
                          Equilibrium constants can be written for acid and base  dissociation reactions.  Water also  autoionizes to form hydrogen and hydroxide ions.  The equilibrium constant for the acid  dissociation reaction ´  the base dissociation constant for the conjugate base = the water dissociation  constant at that temperature. 
                        pH
                          The pH scale is a logarithmic scale to measure the acidity of  a solution.  
  Strong acids and  bases can be assumed to dissociate completely.   Therefore, the concentration of the original strong acid or base is  assumed to equal the concentration of the hydrogen or hydroxide ion.  For weak acids or bases, the equilibrium  constant and ICE charts are used to determine the concentration of the  hydronium ion before solving for pH.
                        Acid/base properties of salts
                          Some salts can have acid/base properties based on the acid or  base they are based off of.  
                          Salts from 
                        
                          
                            - Weak acid + strong base = Basic
 
                            - Weak acid + weak base = Neutral
 
                            - Strong acid + weak base = Acidic
 
                            - Strong acid + Strong base = Neutral
 
                          
                         
                        Buffers
                          A buffer is a solution containing a weak acid and its  conjugate base or a weak base and its conjugate acid.  Buffers resist changes in pH when acids or  bases are added.  The pH will still  change, but much less than if it was plain water.  Buffers use the Henderson-Hasselbach  equation: 
                          
  Titrations
                          Titrations are used to find the concentration of an unknown  solution using a solution of known concentration.  An indicator is used that changes color at  the stoichiometric point (the point at which no reactants are left over) based  on the pH of the products that are in solution at that point.  Stoichiometry is used at that point to  determine the unknown concentration.