Question

An antacid tablet was dissolved in water and 10mL of 0.16M HCl was added. After the acid had reacted with the tablet it required 40mL of 0.02M NaOH to neutralize the HCl that remained. How many moles of HCl did the antacid neutralize

Answer 1

Answer:

0.0008 mole of HCl

Explanation:

From the balanced equation between HCl and NaOH:

$HCl + NaOH --> NaCl + H_2O$

1 mole of acid requires 1 mole of base for neutralization.

mole = molarity x volume

mole of NaOH = 0.02 x 0.04 = 0.0008 mole

mole HCl = 0.16 x 0.01 = 0.0016 mole

Since 1 mole of NaOH requires 1 mole of HCl for neutralization, it means that 0.0008 mole of NaOH will require 0.0008 mole of HCl. The remaining mole of HCl must have been neutralized by the antiacid:

0.0016 - 0.0008 = 0.0008 mole.

Therefore, 0.0008 mole of HCl must have been neutralized by the antiacid.