If 5.30mL of 0.1000 M NaOH solution is needed to just neutralize excess acid after 20.00 mL of 0.1000 M HCl was added to 1.00 g of an antacid, how many moles of acid can the antacid counteract per gram?

1 answer

20.00 x 0.1 = 2.0 millimols initially.
5.30 x 0.1 = 0.530 mmols NaOH for excess.
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2-0.53 = 1.47 millimols acid neutralized by the 1.00 g antacid tablet.
So that would be 0.00147 mols/1 g tab.