Chemistry

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The narcotic drugs relieve pain and produce sleep. Therefore, these are commonly used for the relief of postoperative pain, cardiac pain and pain of terminal cancer and in child birth.

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Narcotic analgesics which are obtained from opium poppy are called opiates. Examples are morphine and its derivatives like codeine and heroin (morphine diacetate).

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Magnesium hydroxide is a better antacid because being insoluble, it does not allow the pH to increase above neutral. However, sodium hydrogen carbonate (NaHCO₃) being soluble, its excess can make the stomach alkaline and trigger the production of even more acid.

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Antiseptics are applied to living tissues whereas disinfectants are applied to non-living objects such as drains, toilets, floors and utensils.

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A person suffers from depression when he has low levels of noradrenaline. Noradrenaline is a neurotransmitter which plays a role in mood changes. Low level of noradrenaline lowers the signal-sending activity and make the person suffer from depression.

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Analgesics are neurologically active pain killing drugs that reduce pain without causing impairment of consciousness, mental confusion, co¬ordination or paralysis or some other disturbances of nervous system. For example, aspirin, ibuprofen, paracetamol, diclofenac sodium, etc.

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Soaps are biodegradable. The detergents are quite stable and are non- biodegradable because of branching in hydrocarbon chain hence cause water pollution. Therefore, it is safer to use soap from the environmental point of view.

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Straight chain hydrocarbons in synthetic detergent leads to easy biodegrad-ability because the branched chain hydrocarbon tail is a source of pollution. Therefore, lesser the branching more is the biodegradability.

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Micelle formation of the detergent can be shown as:

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Non-ionic detergents such as polyethylene glycol stearate are used as dishwashing soaps.