PH PH In chemistry, pH () is a logarithmic scale used to specify the acidity or basicity of an aqueous solution. It is approximately the negative of the base 10 logarithm of the molar concentration, measured in units of moles per liter, of hydrogen ions. More precisely it is the negative of the base 10 logarithm of the activity of the hydrogen ion. At 25 °C, solutions with a pH less than 7 are acidic and solutions with a pH greater than 7 are basic. The neutral value of the pH depends on the temperature, being lower than 7 if the
Dry ice color show is mixed together with the alkali present in the solution, the solution, overall, becomes neutral. HCO + H + NH + OH NH + HCO + HO (addition of ammonia) HCO + H + Na + OH Na + HCO + HO (addition of sodium hydroxide) The color of the solution changes due to the universal indicator, a pH detector. Once the alkali-to-acid universal indicator is incorporated into the solution, the color of the solution changes corresponding to the acidic color of the universal indicator. The color of ammonia and water only is green. However, once the dry ice is