Page 31 - Curriculum Visions Dynamic Book

antacid: a common name for any compound that reacts with stomach acid to neutralise it.
 This demonstration of the reaction of baking powder with vinegar gives an insight into the reaction of an antacid such as baking powder in the stomach. The equation for this reaction is shown below
EQUATION: Baking soda and hydrochloric acid
Stomach acid + sodium bicarbonate ➪ sodium chloride + water + carbon dioxide HCl(aq) + NaHCO3(s) ➪ NaCl(aq) + H2O(l) + CO2(g)
Chlorine Hydrogen
Sodium
Carbon Oxygen
 An antacid tablet is placed into dilute hydrochloric acid as a demonstration of the reaction that takes place inside the stomach. The bubbles of carbon dioxide gas are generated with sufficient vigour to break up the tablet, increasing the area exposed to the acid and thereby speeding up the reaction.
Sodium carbonate and bicarbonate as antacids
Sodium carbonate and bicarbonate are used as antacids to balance the excess of hydrochloric acid that sometimes builds up in the stomach. The sodium carbonate and bicarbonate react with acids to produce a harmless chalk-like material that can be taken away during digestion. Their only side effect is that they give off carbon dioxide gas – which is why people burp when taking this form of antacid.
Sodium bicarbonate as a neutralizer
Baking powder is a mildly alkaline substance that can be used to counteract the sting of a bee.
When a bee stings, it injects an acid just below the skin. This causes the body to react violently, producing pain and severe itching.
The skin is not equipped to send large amounts of an alkali to counteract the acid sting. But baking powder is just one of a number of household substances that can be used to give relief.
If the baking powder is rubbed into the site of the sting, it will react with the acid, neutralising it and making the sting less painful.
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