To get familiar with the recent trend of alkaline water you need to understand some fundamental acid-base chemistry. Alkaline water has a higher pH than other sources of water. The scale for pH ranges from 0 to 14. So, what is pH? It measures the concentration of free hydrogen ions in a solution. The presence of many hydrogen ions makes the solution more acidic, more acidic solution, therefore, has a low PH. Solutions with a small number of hydrogen ions are not acidic and have a higher PH these solutions are called alkaline.