Acid and alkalinity ph value comparison table color card is as follows:

Acid and alkalinity describes the degree of acidity and alkalinity of an aqueous solution, expressed in terms of pH. Thermodynamic standard condition, pH = 7 of the aqueous solution is neutral, pH & lt; 7 is acidic, pH & gt; 7 is alkaline.

PH ranges from 0 to 14 and applies only to dilute solutions; the acidity or alkalinity of solutions with a hydrogen ion concentration or hydroxide ion concentration greater than 1 mol/L is expressed directly in terms of concentration.

Expanded information:

In non-aqueous solutions or at non-standard temperatures and pressures, pH=7 may not mean that the solution is neutral, and it is necessary to determine the value at which the pH is neutral by calculating the ionization constant of that solvent under such conditions. For example, at a temperature of 373 K (100 °C), the pH of a neutral solution is ≈ 6.

Additionally, it should be noted that the effective number of pH is recorded from the end of the decimal point, and the portion before the decimal point is an exponent, which cannot be recorded as an effective number.

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