AntacidsChemistry Option D 2.1.

• Antacid is a mechanism. It performs a neutralization reaction on gastric acid.

• They act as a buffer, agents which adjust the pH level of a solution.

• Gastric acid is a secretion produced in the stomach. It is an acidic solution (pH level 1 to 2) consists of HCl and KCl.

• The main task of antacids is raising the pH level to reduce acidity in the stomach.

• The reasons we would want that, is that the stomach would immediately dissolve itself because of the high acidity.

• The gastrointestinal mucosa therefore releases a mucus, which prevents that.

• This mucus contains antacids. It contains Sodium Hydrogen carbonate, NaHCO3.

• You can develop Peptic Ulcers, which are an erosion of the mucosa. When gastric HCl reaches the nerves in the mucosa, the nerves signal pain.

• It may also reach ulcers in the esophagus or the duodenum.

• For that to happen, you need a pylorus infection. The openings of the stomach do not close properly and gastric acids can escape.

• You can also suffer from Reflux.

• When gastric acid escapes into the esophagus, we talk of heartburn, pyrosis. It is called that way because it is described as a burning pain in the chest.

• To treat all of those conditions, you can take medicaments, as a liquid or in tablet form. For example, Maalox, Alka-Seltzer or Milk of Magnesia.

• Those medicaments work by Acid – Base reactions. To neutralize the gastric acid, bases are used. The most popular, are Aluminium and Magnesium compounds and Sodium Hydrogen carbonate.

• For example, Maalox is made up out of a compound of Al(OH)3 and Mg(OH)2.

Compound Chem. formula

Chem. reaction

Aluminium hydroxide

Al(OH)3Al(OH)3 + 3HCl AlCl3 + 3H2O

Calcium carbonate

CaCO3CaCO3 + 2HCl CaCl2 + H2O + CO2

Magnesium carbonate

MgCO3MgCO3 + 2HCl MgCl2 + H2O + CO2

Magnesium hydroxide

Mg(OH)2Mg(OH) + 2HCl MgCl2 + 2H2O

Sodium bicarbonate

NaHCO3NaHCO3 + HCl NaCl + H2O + CO2

• Common side effects of those drugs are problems in digestion. For example, diarrhea, constipation or flatulence.

• More serious side effects can include kidney damage or internal bleedings.

• Problems of a higher pH level of the gastric acid are an impaired ability to digest and absorb certain nutrition. Since the low pH level of the gastric acid kills bacteria, antacids increase the risk of infections.