pH of solution A is 12.5 and it is the most basic (alkaline) among all.
Those solution which are having value more than 7 in the pH scale shows the basic character and relation between pH & pOH will be represented as:
pH + pOH = 14
Now we calculate the pH for given solutions:
For solution A, pOH = 1.5
pH = 14 - 1.5 = 12.5
For solution B, pOH = 7
pH = 14 - 7 = 7
For solution C, pOH = 13.5
pH = 14 - 13.5 = 0.5
Value of pH for solution A is highest and shows basic nature, solution B is neutral and solution C is acidic in nature.
Hence, solution A is most basic.
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