The pH scale is a tool that measures how acidic or basic a liquid solution is, running from 0 to 14. The letters pH stand for "potential of hydrogen" or "power of hydrogen".  The scale goes from 0 to 14. Neutral (7): Pure water, Table salt (Sodium chloride / NaCl), Sugar solution. Acidic (Below 7): Lemon juice, Vinegar, Hydrochloric acid (HCl) Basic / Alkaline (Above 7): Baking soda, Soap, Sodium hydroxide (NaOH)