Chemical Reactions and Equations

1. A.
   The combustion of natural gas
2. B.
   The reaction of a reactive metal with dilute acid
3. C.
   The electrolysis of water
4. D.
   The reaction of quick lime with water

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1. A.
   2, 2
2. B.
   1, 2
3. C.
   2, 1
4. D.
   1, 1

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1. A.
   (i) is double displacement, (ii) is displacement reaction.
2. B.
   Both, (i) and (ii) are displacement reactions and precipitation reactions.
3. C.
   Both, (i) and (ii) are double displacement reactions and precipitation reactions.
4. D.
   (i) is displacement, (ii) is double displacement reaction.

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1. A.
   brown fumes of $\mathrm{O_2}$ gas
2. B.
   white fumes of $\mathrm{NO_2}$ gas
3. C.
   yellow fumes of lead oxide
4. D.
   brown fumes of $\mathrm{NO_2}$ gas

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1. A.
   1 : 2
2. B.
   2 : 1
3. C.
   1 : 3
4. D.
   4 : 1

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1. A.
   1 : 1
2. B.
   2 : 1
3. C.
   4 : 1
4. D.
   1 : 2

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1. A.
   (i) and (iii)
2. B.
   (iii) and (iv)
3. C.
   (ii) and (iv)
4. D.
   (ii) and (iii)

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1. A.
   Displacement Reaction
2. B.
   Endothermic Reaction
3. C.
   Exothermic Reaction
4. D.
   Neutralisation Reaction

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1. A.
   A colourless gas with no smell is evolved.
2. B.
   A brown gas is evolved.
3. C.
   The green colour of the salt fades and a gas with the smell of burning sulphur is evolved.
4. D.
   The green colour of the salt fades and no gas is evolved.

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1. A.
   (i) and (ii)
2. B.
   (iii) and (iv)
3. C.
   (i) and (iii)
4. D.
   (ii) and (iv)

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1. A.
   $\mathrm{NO}$ and $\mathrm{O_2}$
2. B.
   $\mathrm{N_2}$ and $\mathrm{NO_2}$
3. C.
   $\mathrm{NO_2}$ and $\mathrm{H_2}$
4. D.
   $\mathrm{NO_2}$ and $\mathrm{O_2}$

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1. A.
   The polish over the jewellery was removed after wearing for a few months.
2. B.
   The jewellery comes in contact with air, moisture and acids and corrodes.
3. C.
   Dust particles over the jewellery change its colour.
4. D.
   Its colour changes due to rusting.

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1. A.
   Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
2. B.
   Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
3. C.
   Assertion (A) is true, but Reason (R) is false.
4. D.
   Assertion (A) is false, but Reason (R) is true.

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1. A.
   (i) and (ii)
2. B.
   (iii) and (iv)
3. C.
   (i) and (iii)
4. D.
   (ii) and (iv)

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1. A.
   3, 2, 2, 1
2. B.
   2, 3, 3, 1
3. C.
   2, 3, 1, 3
4. D.
   3, 1, 2, 2

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1. A.
   Milk is left open at room temperature during summer
2. B.
   Grapes get fermented
3. C.
   An iron nail is left exposed to humid atmosphere
4. D.
   Melting of glaciers

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1. A.
   $\mathrm{CH_4 + O_2 \rightarrow CO_2 + 2H_2O}$
2. B.
   $\mathrm{CH_4 + 2O_2 \rightarrow 2CO_2 + 2H_2O}$ + Energy
3. C.
   $\mathrm{CH_4 + 2O_2 \rightarrow CO_2 + 2H_2O}$
4. D.
   $\mathrm{CH_4 + 2O_2 \rightarrow CO_2 + 2H_2O}$ + Energy

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1. A.
   (i) and (ii)
2. B.
   (ii) and (iii)
3. C.
   (iii) and (iv)
4. D.
   (ii) and (iv)

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1. A.
   8 : 1
2. B.
   2 : 1
3. C.
   1 : 2
4. D.
   1 : 8

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1. A.
   (i) and (iv)
2. B.
   (ii) and (iii)
3. C.
   (i) and (ii)
4. D.
   (iii) and (iv)

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1. A.
   1 : 2
2. B.
   1 : 4
3. C.
   1 : 8
4. D.
   1 : 16

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1. A.
   It burns with a dazzling white flame.
2. B.
   A white powder is formed on burning.
3. C.
   It is an endothermic reaction.
4. D.
   It is an example of a combination reaction.

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1. A.
   1, 1, 2, 1
2. B.
   1, 1, 1, 2
3. C.
   2, 2, 1, 4
4. D.
   2, 2, 4, 1

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1. A.
   Blue
2. B.
   Pale green
3. C.
   Yellow
4. D.
   Reddish brown

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1. A.
   Both, Assertion (A) and Reason (R) are true, and Reason (R) is the correct explanation of Assertion (A).
2. B.
   Both, Assertion (A) and Reason (R) are true, and Reason (R) is not the correct explanation of Assertion (A).
3. C.
   Assertion (A) is true, but Reason (R) is false.
4. D.
   Assertion (A) is false, but Reason (R) is true.

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1. A.
   Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of Assertion (A).
2. B.
   Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of Assertion (A).
3. C.
   Assertion (A) is true, but Reason (R) is false.
4. D.
   Assertion (A) is false, but Reason (R) is true.

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1. A.
   Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
2. B.
   Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
3. C.
   Assertion (A) is true, but Reason (R) is false.
4. D.
   Assertion (A) is false, but Reason (R) is true.

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1. A.
   blue deposit
2. B.
   brown deposit
3. C.
   grey deposit
4. D.
   green deposit

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1. A.
   Endothermic Reaction
2. B.
   Exothermic Reaction
3. C.
   Double Displacement Reaction
4. D.
   Displacement Reaction

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1. A.
   is endothermic and pH of the solution formed is more than 7.
2. B.
   is exothermic and pH of the solution formed is 7.
3. C.
   is endothermic and pH of the solution formed is 7.
4. D.
   is exothermic and pH of the solution formed is more than 7.

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1. A.
   4, 2, 2
2. B.
   4, 4, 2
3. C.
   2, 2, 4
4. D.
   2, 4, 2

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1. A.
   $\mathrm{2\,FeSO_4 \longrightarrow Fe_2O_3 + SO_2 + SO_3}$
2. B.
   $\mathrm{CaCO_3 \longrightarrow CaO + CO_2}$
3. C.
   $\mathrm{2\,AgCl \longrightarrow 2\,Ag + Cl_2}$
4. D.
   $\mathrm{Pb(NO_3)_2 \longrightarrow 2\,PbO + 4\,NO_2 + O_2}$

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1. A.
   Decomposition reaction
2. B.
   Displacement reaction
3. C.
   Double displacement reaction
4. D.
   Combination reaction

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1. A.
   Quick lime
2. B.
   Gypsum
3. C.
   Lime Stone
4. D.
   Plaster of Paris

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1. A.
   $\mathrm{2FeSO_4 \rightarrow Fe_2O_3 + SO_2 + SO_3}$
2. B.
   $\mathrm{2H_2O \rightarrow 2H_2 + O_2}$
3. C.
   $\mathrm{2AgBr \rightarrow 2Ag + Br_2}$
4. D.
   $\mathrm{CaCO_3 \rightarrow CaO + CO_2}$

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1. A.
   $\mathrm{C + O_2 \rightarrow CO_2}$
2. B.
   $\mathrm{2\,H_2 + O_2 \rightarrow 2\,H_2O}$
3. C.
   $\mathrm{2\,Mg + O_2 \rightarrow 2\,MgO}$
4. D.
   $\mathrm{Fe_2O_3 + 3\,CO \rightarrow 2\,Fe + 3\,CO_2}$

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1. A.
   Burning of coal
2. B.
   Decomposition of vegetable matter into compost
3. C.
   Process of respiration
4. D.
   Decomposition of calcium carbonate to form quick lime and carbon dioxide.

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1. A.
   Black and White photography
2. B.
   Burning of coal
3. C.
   Burning of methane
4. D.
   Digestion of food

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1. A.
   1, 6, 2 and 3
2. B.
   1, 6, 3 and 2
3. C.
   2, 6, 2 and 3
4. D.
   2, 6, 3 and 2

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1. A.
   $\mathrm{PbO}$, $\mathrm{N_2O}$ and $\mathrm{O_2}$
2. B.
   $\mathrm{NO}$, $\mathrm{PbO}$ and $\mathrm{O_2}$
3. C.
   $\mathrm{Pb(NO_2)_2}$ and $\mathrm{O_2}$
4. D.
   $\mathrm{NO_2}$, $\mathrm{PbO}$ and $\mathrm{O_2}$

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1. A.
   $\mathrm{H_2S}$ is oxidising agent and $\mathrm{SO_2}$ is reducing agent.
2. B.
   $\mathrm{H_2S}$ is reduced to sulphur.
3. C.
   $\mathrm{SO_2}$ is oxidising agent and $\mathrm{H_2S}$ is reducing agent.
4. D.
   $\mathrm{SO_2}$ is oxidised to sulphur.

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1. A.
   $\mathrm{NaCl + AgNO_3 \rightarrow AgCl + NaNO_3}$
2. B.
   $\mathrm{CaO + H_2O \rightarrow Ca(OH)_2}$
3. C.
   $\mathrm{KNO_3 + H_2SO_4 \rightarrow KHSO_4 + HNO_3}$
4. D.
   $\mathrm{ZnCl_2 + H_2S \rightarrow ZnS + 2HCl}$

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1. A.
   $\mathrm{MnO_2}$ is oxidised and HCl is reduced.
2. B.
   HCl is oxidised.
3. C.
   $\mathrm{MnO_2}$ is reduced.
4. D.
   $\mathrm{MnO_2}$ is reduced and HCl is oxidised.

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1. A.
   Both (A) and (R) are true and (R) is the correct explanation of (A).
2. B.
   Both (A) and (R) are true and (R) is not correct explanation of (A).
3. C.
   (A) is true, but (R) is false.
4. D.
   (A) is false, but (R) is true.

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1. A.
   Formation of slaked lime
2. B.
   Decomposition of vegetable matter into compost
3. C.
   Dissolution of ammonium chloride in water
4. D.
   Digestion of food in our body

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1. A.
   4
2. B.
   2
3. C.
   $\frac{1}{2}$
4. D.
   $\frac{1}{4}$

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1. A.
   1, 4
2. B.
   1, 2
3. C.
   2, 4
4. D.
   2, 3

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1. A.
   $\mathrm{KI + PbNO_3 \longrightarrow PbI + KNO_3}$
2. B.
   $\mathrm{2KI + Pb(NO_3)_2 \longrightarrow PbI_2 + 2KNO_3}$
3. C.
   $\mathrm{KI + Pb(NO_3)_2 \longrightarrow PbI + KNO_3}$
4. D.
   $\mathrm{KI + PbNO_3 \longrightarrow PbI_2 + KNO_3}$

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1. A.
   thermal decomposition of lead nitrate which produces brown fumes of nitrogen dioxide.
2. B.
   thermal decomposition of lead nitrate which produces brown fumes of lead oxide.
3. C.
   oxidation of lead nitrate forming lead oxide and nitrogen dioxide.
4. D.
   oxidation of lead nitrate forming lead oxide and oxygen.

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1. A.
   $\mathrm{2\,CaO + H_2O \longrightarrow 2\,CaOH + H_2}$ + Heat
2. B.
   $\mathrm{CaO + H_2O \longrightarrow Ca(OH)_2 + H_2}$ + Heat
3. C.
   $\mathrm{CaO + H_2O \longrightarrow Ca(OH)_2}$ + Heat
4. D.
   $\mathrm{2\,CaO + 3\,H_2O \longrightarrow 2\,Ca(OH)_3 + O_2}$ + Heat

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1. A.
   6, 2, 2
2. B.
   4, 1, 2
3. C.
   4, 2, 1
4. D.
   2, 2, 1

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1. A.
   Na
2. B.
   $\mathrm{H_2O}$
3. C.
   NaOH
4. D.
   $\mathrm{H_2}$

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1. A.
   X: (s); Y: (l)
2. B.
   X: (aq); Y: (g)
3. C.
   X: (aq); Y: (s)
4. D.
   X: (g); Y: (aq)

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1. A.
   2, 4
2. B.
   2, 2
3. C.
   2, 3
4. D.
   4, 2

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1. A.
   X = $\mathrm{Ca}$ ; Y = $\mathrm{CaO}$ ; Type of reaction = Decomposition
2. B.
   X = $\mathrm{Mg}$ ; Y = $\mathrm{MgO}$ ; Type of reaction = Combination
3. C.
   X = $\mathrm{Al}$ ; Y = $\mathrm{Al_2O_3}$ ; Type of reaction = Thermal decomposition
4. D.
   X = $\mathrm{Zn}$ ; Y = $\mathrm{ZnO}$ ; Type of reaction = Endothermic

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1. A.
   Decomposition of vegetable matter into compost.
2. B.
   Decomposition of calcium carbonate to form quick lime and carbon dioxide.
3. C.
   Burning of a candle.
4. D.
   Process of respiration.

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1. A.
   ‘I’ is a displacement reaction and ‘II’ is a decomposition reaction.
2. B.
   ‘I’ is a displacement reaction and ‘II’ is double displacement reaction.
3. C.
   Both ‘I’ and ‘II’ are displacement reactions.
4. D.
   Both ‘I’ and ‘II’ are double-displacement reactions.

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1. A.
   Both (A) and (R) are true and (R) is the correct explanation of (A).
2. B.
   Both (A) and (R) are true but (R) is not the correct explanation of (A).
3. C.
   (A) is true but (R) is false.
4. D.
   (A) is false but (R) is true.

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1. A.
   Both Assertion (A) and Reason (R) are true and Reason (R) is the correct explanation of the Assertion (A).
2. B.
   Both Assertion (A) and Reason (R) are true, but Reason (R) is not the correct explanation of the Assertion (A).
3. C.
   Assertion (A) is true, but Reason (R) is false.
4. D.
   Assertion (A) is false, but Reason (R) is true.

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