You have two beakers. One beaker contains 100 mL of NaOH (a strong base); the other contains 100 mL of aqueous Na3PO4 (a weak base). You test the pH of each solution. Which of the following statements is true ?

The question lack options, that are as follows"

The following statements are true in the given question:

We know that:

Again,

PH +POH =14

From the above equation,

So,

Thus, If pH NaOH = 12.00, NaOH is a strong base and Na3PO4 is a weak base. For the solution, the weak base OH-ion concentration is less. Clearly, the pH of Na3PO4 is less than 12.00.

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D. If the pH of NaOH is 12, then that of Na₃PO₄ solution has to be lesser than 12.

Explanation:

In this problem, we are comparing the pH of a strong base to a weak base. A strong base is one that ionizes completely in aqueous solutions where as a weak base ionizes slightly.

The pH scale is good tool for measuring the acidity and alkalinity of various substances. It ranges from 1 - 14;

      1                                      7                                               14

                         ←                                       →

      increasing acidity                          increasing alkalinity

                                        neutrality

Strong bases have their pH value close to 14 and weak bases are close to 7.

Since Na₃PO₄ is a weak base, it will have lesser pH value compared to a strong base such as NaOH