Volumetric analysis
exercise 8
A tablet of the antacid Milk Of Magnesia contains 0.45g of magnesium hydroxide. Assuming that the stomach fluid contains 0.15M hydrochloric acid solution calculate the volume of stomach fluid that one tablet can neutralise.
( Atomic mass of Mg = 24.3, H = 1, O =16, C =12)
The equation for the reaction is shown below.
Step 1 Calculate
the mole of magnesium hydroxide
Mole = mass / formula mass
Mole = 0.45 / 58.3 =0.0077 mole
Step 2 Using
the equation calculate the number of mole of HCl required to react completely
For every one mole of magnesium hydroxide two mole of HCl react.
So
mole of HCl = 0.0077 X 2 =0.0154 mole
Step 3 Find
the volume of HCl solution(stomach fluid)
volume =mole / concentration
Volume = 0.0154 / 0.15 = 0.103 litres