Chemistry miscellaneous
- Soap is prepared by boiling caustic soda with
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The most basic kind of soap is made from cuastic soda and animal fat. The two are heated together, and then cooled. The process is called “saponification”. In technical terms, saponification involves base (usually caustic soda NaOH) hydrolysis of triglycerides, which are esters of fatty acids, to form the sodium salt of a carboxylate.
Correct Option: D
The most basic kind of soap is made from cuastic soda and animal fat. The two are heated together, and then cooled. The process is called “saponification”. In technical terms, saponification involves base (usually caustic soda NaOH) hydrolysis of triglycerides, which are esters of fatty acids, to form the sodium salt of a carboxylate.
- Which of the following gases is mixed with oxygen for breathing by divers in aqualungs?
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For some diving, gas mixtures other than normal atmospheric air (21% oxygen, 78% nitrogen, 1% trace gases) can be used, so long as the diver is properly trained in their use. The most commonly used mixture is Nitrox, also referred to as Enriched Air Nitrox (EAN), which is air with extra oxygen, often with 32% or 36% oxygen, and thus less nitrogen, reducing the likelihood of decompression sickness or allowing longer exposure to the same pressure for equal risk.
Correct Option: B
For some diving, gas mixtures other than normal atmospheric air (21% oxygen, 78% nitrogen, 1% trace gases) can be used, so long as the diver is properly trained in their use. The most commonly used mixture is Nitrox, also referred to as Enriched Air Nitrox (EAN), which is air with extra oxygen, often with 32% or 36% oxygen, and thus less nitrogen, reducing the likelihood of decompression sickness or allowing longer exposure to the same pressure for equal risk.
- Conversion of chemical energy into electrical energy occurs in
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A battery is a form of chemical energy that can be converted to electrical energy. it is a device consisting of one or more electrochemical cells which performs this action. The first battery (or "voltaic pile") was invented in 1800 by Alessandro Volta.
Correct Option: C
A battery is a form of chemical energy that can be converted to electrical energy. it is a device consisting of one or more electrochemical cells which performs this action. The first battery (or "voltaic pile") was invented in 1800 by Alessandro Volta.
- Urea is a
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More than 90% of world production of urea is destined for use as a nitrogen-release fertilizer. Urea has the highest nitrogen content of all solid nitrogenous fertilizers in common use.
Correct Option: C
More than 90% of world production of urea is destined for use as a nitrogen-release fertilizer. Urea has the highest nitrogen content of all solid nitrogenous fertilizers in common use.
- In vulcanisation process, rubber can be hardened by adding
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In order to give more strength and more elasticity, natural rubber is heated with sulphur or sulphur compounds at 150°C temperature. Vulcanized rubber has good tensile strength.
Correct Option: C
In order to give more strength and more elasticity, natural rubber is heated with sulphur or sulphur compounds at 150°C temperature. Vulcanized rubber has good tensile strength.