Science
(a) Suggest one remedial measure each to counteract the change in pH in human beings in following cases :
(i) Production of too much acid in stomach during indigestion
(ii) Stung by a honey bee / nettle leaves
(b) Fresh milk has a pH of 6. When it changes into curd will its pH increase or decrease ? Why ?
Answer
(a) (i) Production of too much acid in stomach during indigestion leads to pain and irritation. Antacid is given in such case to neutralize the acid of the stomach. The antacids neutralise the excess acid. Magnesium hydroxide (milk of magnesia) is a mild base, often used for this purpose.
(ii) In case of a honeybee sting formic acid is released into the skin which causes pain and irritation. To reduce the pain caused due to the sting, bases like baking soda are used which neutralize acid and relieve the pain. Stinging hair of nettle leaves inject methanoic acid causing burning pain. It is also treated with rubbing mild base.
(b) When the milk is turned into curd then its pH value decreases. This is due to the production of lactic acid in curd which is acidic in nature.
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