A Solution with a PH of 9 Has ____ Times

Question

A solution with a pH of 9 has ____ times fewer hydrogen ions than a solution with a pH of 6.  
A) two
B) four
C) 10
D) 100
E) 1,000

Accepted Answer

The pH scale is logarithmic, meaning each whole pH value below 7 is ten times more acidic (or has ten times more hydrogen ions) than the next higher value. Therefore, a solution with a pH of 6 has 1,000 (10^3) times more hydrogen ions than a solution with a pH of 9.