If the pH of aqueous solutions A, B, C and D are 1.9, 2.5, 2.1 and 3.0 then what will be the order of acidity ?

As the concentration of H ⁺ ions increase, the acidity increases, and the pH decreases. Thus, we can say that lesser the pH more will be the acidity. Therefore, solution A will have maximum acidity as it has the least pH followed by solution C, followed by solution B and solution D is least acidic as it has a maximum pH of 3.

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