Continuing into the world of acids and bases…

 pH of a solution is the negative logarithm of the hydrogen ion concentration  pH = -log [H + ]  This number represents how strong or weak an acid/base is

 The pH scale ranges from 1-14  pH less than 7 is an acid  the lower pH = the stronger the acid  pH greater than 7 is a base  the higher the pH = the stronger the base

 Find the pH if the hydrogen concentration are as follows:  a) 1.0 x M  b) 3.0 x M  c) M

pOH = - log [OH - ]  Everything is the opposite  pOH less than 7 = base  The lower the pOH, stronger the base  pOH greater than 7 = acid  The higher the pOH, stronger the acid

 Find the pOH for the following hydroxide concentrations:  a) 1.0 x M  b) M

pH + pOH = 14  Find the pH if a solution has the following hydroxide concentration: [OH - ] = 8.2 x M

 What if you are given the pH and want to find the concentration of hydrogen ions? [H + ] = 10 -pH

 1) What is the [H + ] if the pH is 8.9?  2) What about if the pH is 2.3?

K w = 1.0x M 1.0 x = [H + ] [OH - ]