A solution with a pH of 6 is acidic. a solution is considered acidic when the pH<7 while a solution is considered basic when the pH>7 (a neutral solution has a pH=7).
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From 15 mol of Silver nitrate, the moles of silver chloride produced have been 15 mol. Thus, option B is correct.
The balanced chemical reaction for the synthesis of silver chloride has been:

From the balanced equation, since there has presence equal moles of silver nitrate and sodium chloride, the moles of silver chloride formed has been equivalent. Thus, 1 mole of silver nitrate gives 1 mole of silver chloride.
The moles of silver nitrate available are, 
The moles of silver nitrate produced can be given as:

Thus, the moles of silver chloride produced have been 15 mol. Thus, option B is correct.
For more information about moles produced, refer to the link:
brainly.com/question/10606802
All solutions are mixtures