1. A
   $H_2$ is lighter than air and insoluble in water.
2. B
   $H_2$ is inert at room temperature due to high H – H bond dissociation enthalpy.
3. C
   $H_2$ reacts with alkali metals at high temperature to yield metal hydrides.
4. D
   A mixture of $NO_2$ and $H_2$ is known as Syngas.

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1. A
   Na, Mg, Ca
2. B
   Na, Mg, Al
3. C
   Mg, Ca, K
4. D
   Mg, Ca, Ba

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1. A
   0° Celsius
2. B
   – 073° Celsius
3. C
   – 173° Celsius
4. D
   – 273° Celsius

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1. A
   – 40°
2. B
   0°
3. C
   – 273°
4. D
   100°

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1. A
   real and thus can be photographed.
2. B
   virtual and nearer than the object.
3. C
   virtual and is laterally inverted.
4. D
   real but cannot be photographed.

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1. A
   Blue
2. B
   Magenta
3. C
   Pink
4. D
   Yellow

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1. A
   Yellow, Red and Green
2. B
   Blue, Red and Green
3. C
   Violet, Red and Yellow
4. D
   Indigo, Violet and Green

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1. A
   It applies only to spherical mirrors.
2. B
   It applies only to spherical lenses.
3. C
   It applies to spherical mirrors as well as spherical lenses.
4. D
   It is an invalid formula.

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1. A
   Ribosomes.
2. B
   Mitochondria.
3. C
   Lysosomes.
4. D
   Endoplasmic reticulum.

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1. A
   Outer membrane.
2. B
   Matrix.
3. C
   Inner membrane.
4. D
   DNA of mitochondria.

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1. A
   Oesophagus.
2. B
   Small intestine.
3. C
   Ducts of salivary gland.
4. D
   Kidney.

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1. A
   Cell differentiation.
2. B
   Cell division.
3. C
   Cell multiplication.
4. D
   Cell regeneration.

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1. A
   Respiration and Nitric oxide
2. B
   Transpiration and Water vapour
3. C
   Photosynthesis and Oxygen
4. D
   Germination and Carbon dioxide

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1. A
   Experimental leaf 1
2. B
   Experimental leaf 2
3. C
   Control leaf
4. D
   All the leaves will dry up simultaneously

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1. A
   Light travels at different speeds in different media.
2. B
   Light travels at almost 300 million metres per second in air.
3. C
   Light speeds down as it leaves a water surface and enters the air.
4. D
   Light speeds up as it leaves a glass surface and enters the air.

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1. A
   Red light will deviate the most and it is because of the reflection of light.
2. B
   Violet light will deviate the most and it is because of the refraction of light.
3. C
   Red light will deviate the most and it is because of the refraction of light.
4. D
   Violet light will deviate the most and it is because of the reflection of light.

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1. A
   0·1 C
2. B
   10 C
3. C
   600 C
4. D
   800 C

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1. A
   $I^2 R$
2. B
   $IR^2$
3. C
   $VI$
4. D
   $V^2/R$

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1. A
   Reverberation.
2. B
   Dispersion.
3. C
   Refraction.
4. D
   Diffraction.

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1. A
   Rayleigh scattering.
2. B
   Raman effect.
3. C
   Photoelectric effect.
4. D
   Rutherford scattering.

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1. A
   The oil and dirt gets collected in the centre of the micelle.
2. B
   Soap micelles scatter light.
3. C
   Soaps are ammonium salts of long chain carboxylic acids.
4. D
   Soap forms insoluble precipitates with the calcium and magnesium ions in hard water.

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1. A
   Substitution reaction.
2. B
   Elimination reaction.
3. C
   Addition reaction.
4. D
   Free-radical polymerization.

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1. A
   Diamond
2. B
   Graphene
3. C
   Fly ash
4. D
   Fullerene

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1. A
   Reaction of zinc metal with dilute sulphuric acid solution
2. B
   Mixing water to Plaster of Paris
3. C
   Heating zinc metal with sodium hydroxide solution
4. D
   Reaction of potassium metal with water

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1. A
   Acetic acid
2. B
   Tartaric acid
3. C
   Oxalic acid
4. D
   Lactic acid

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