Gastric juice contains 2.98 g HCL per liter. If a person produces about 2.5 L of gastric juice per day, how many antacid tablets, each containing 400 mg of Al(OH)3 are needed to neutralize all the HCL produced in one day?
Balanced the reaction is Al(OH)3+3HCl--->AlCl3+3H2O
`Al(OH)_3+3HCl rarr AlCl_3+3H_2O`
So to neutralize 3 HCl moles we need 1 mole of `Al(OH)_3` .
Amount of HCl in 1L of gastric juice `= 2.98g`
Amount of HCl in 2.5L of gastric juice `= 2.98xx2.5 = 7.45g`
So per day a person will produce 7.45g of HCl.
Molic weight of HCl `= 36.5g/(mol)`
Amount of HCl moles produced per day `= 7.45/36.5`
Amount of HCl moles produced per day `= 0.204`
`Al(OH)_3:HCl = 1:3`
Amount of `Al(OH)_3` moles needed `= 0.204/3 = 0.068`
Molic weight of `Al(OH)_3 = 78g/(mol)`
Weight of `Al(OH)_3` needed to neutralize HCl ` `
`= 5.304g `
Amount of antacid tablets needed
`= 5304/400 `
So the person need to get 14 tablets per day to neutralize the HCl acid.