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Chemistry
211)A dark-purple compound used as an antiseptic and disinfectant is
	sodium thiosulphate		potassium nitrate
	patassium permanganate		calcium phosphate
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212)Alloy steel containing chromium to resist rusting is known as
	hard steel		stainless steel
	cast iron		wrought iron
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213)The point at which the solid, liquid and gaseous forms of substance co-exist is called
	melting point		boiling point
	triple point		freezing point
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214)Pencil lead is made up of
	graphite		manganese dioxide
	charcoal		lampblack
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215)Antibodies is the name given to
	substances formed in the blood that inhibit or destroy harmful bactirial attacks		harmful bacteria
	viruses that causes infection		poisonous substances
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216)A medicinal substance given against the intake of poisons or to prevent a disease from having an effect is known as an
	antigen		antibody
	antidote		antibiotic
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217)The process of elemination of water from any system is called
	reduction		oxidation
	evaporation		dehydration
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218)Haemoglobin is
	a compound that transmits signals to the brain		the colouring of leaves of plants
	a compound present in the heart		the colouring matter of the red corpuscles in blood
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219)Riboflavin is a (an)
	plant		vitamin
	antibiotic		colouring matter
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220)The gas emitted by burning wood is mainly
	carbon monoxide		carbon dioxide
	sulphur dioxide		methane
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221)The substance that causes the worst air polution is
	carbon dioxide		sulphur dioxide
	carbon monoxide		smoke
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222)Petroleum is found in
	sedimentary rock		metamorphic rock
	marshy land		igneous rock
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223)The substance that contains the maximum amount of nitrogen is
	urea		ammonium nitrate
	ammonium chloride		ammonium sulphate
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224)The disease Beri-Beri is caused by the deficiency of
	hormone		iron
	vitamin B		iodine
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225)Sweat contains
	phosphoric acid		pure water
	calcium phosphate and water		water, salt and waste matter
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