PH


  In physicochemistry, pH is by definition the colog of the hydrogen ionic concentration of the medium, which indicates the acidity or basicity of an aqueous solution.
  The higher the number of hydrides there is in the medium, the more acidic, and the more OH ions, the more basic or alkaline will be the solution.
  Acid: [H +] maior que [OH-]; It is every substance that in the aqueous solution ionizes releasing in cation H.
  Basic: [H +] menor que [OH-]; It is every substance that in aqueous solution dissociates releasing an OH anion.
  PH Scale: Scale representation where a neutral solution equals seven, values less than seven indicate an acid solution and those greater than seven indicate a basic solution.
 Referencia: BRADY, J.E. & HUMISTON, G.E. Química Geral. 2. ed. Rio de Janeiro: LTC Editora, 1986.

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