The pH scale is in terms of a logarithmic scale, so as you go down on the pH scale, the acidity increases by a power of ten. So since 6 is 4 away from 2, 10 to the fourth power is 10000 meaning a solution with a pH of 2 is 10000 times more acidic than one with a pH of 6.It is backwards for basic. As you go up on the pH scale, it increases by a power of ten. So a pH of 13 is 1000 more basic than a pH of 10