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What is pH?

pH may be seen as an abbreviation of the power of hydrogen-or, more fully, the concentration of hydrogen ions in a liquid. The mathematical definition of the Power of Hydrogen is a little less intuitive but more useful in general. It states that the Power of Hydrogen equals the negative logarithmic value of the concentration of hydrogen ion (H+)

Importance of pH

  • We know that our stomach contains hydrochloric acid which helps in the digestion of food. When the stomach produces too much hydrochloric acid during indigestion, we feel a lot of pain and irritation. Hence, we generally use antacids or a mild base which increases the pH of the acidic stomach and thus decreases the pain.
  • Bacteria present in our mouth sometimes lower the pH of our mouth by producing acids through degradation of the food particle. Hence, we are instructed to clean our mouths with toothpaste (which is generally basic) to prevent their decay by maintaining the pH.
  • We experience a lot of pain in the case of bee-sting as the bee injects the methanoic acid through its sting. Hence, we are generally advised to apply baking soda or other mild bases on the surface as it helps in maintaining the pH of the surface.

pH Chemistry

A Power of Hydrogen scale is a tool for measuring acids and bases. Ex: Vinegar is an acid and measures 2.4 on the pH scale. A healthy Power of Hydrogen balance plays a significant role in your overall well-being, and doctors and scientists usually agree on this. The pH level, or possible level of hydrogen, in your body is determined by the food and type of drink you consume. The pH is the concentration of the hydrogen ions. This calculation is based on a 0 to 14 scale.

pH Value-colour-variation

Power of Hydrogen = -log [H+]

A water source‘s Power of Hydrogen value is a function of its acidity or alkalinity. The pH level is a function of the hydrogen atom activity, as the hydrogen activity is a reasonable indicator of the water’s acidity or alkalinity. As seen below, the Power of Hydrogen scale ranges from 0 to 14 when 7.0 is neutral. It is said that water with a low Power of Hydrogen is acidic and that water with a high Power of Hydrogen is basic, or alkaline. Pure water should have a pH of 7.0 however, due to pollutants in the water, water supplies and precipitation appear to be slightly acidic.

Power of Hydrogen Value

  • If [H+] > 10-7, the Power of Hydrogen is less than 7 and the solution is acidic.
  • If [H+] = 10-7, the Power of Hydrogen is 7 and the solution is neutral.
  • If [H+] < 10-7, more than 7 and the solution is basic.