Available Answers

1. 1.

   SELECT THE CORRECT ANSWER/S - from the choices in each case

   1. The gas which gives a white precipitate when bubbled into a clear filtered solution of slaked lime dissolved in water.
      1. NH₃
      2. CI₂
      3. O₂
      4. CO₂
      5. NO₂
   2. The gas which oxidizes a foul smelling gas to form yellow particles of sulphur as the oxidized product.
      1. NO₂
      2. O₂
      3. CI₂
      4. NH₃
      5. H₂
   3. The gas which combines with hydrogen chloride gas to give dense white fumes of a solid suspended in air. The solid on heating sublimes leaving no residue.
      1. CO₂
      2. CI₂
      3. O₂
      4. NH₃
      5. H₂S
   4. The gas which is non-combustible, supports combustion and reacts with nitric oxide to give a coloured acidic gas.
      1. SO₂
      2. NO₂
      3. H₂
      4. CI₂
      5. O₂
   5. The gas which is heavier than air, fairly soluble in water, non-combustible and a non-supporter of combustion and burning magnesium burns in it forming a white oxide leaving behind black particles.
      1. SO₂
      2. CO₂
      3. NO₂
      4. CI₂
      5. O₂
   6. A substance which on heating leaves behind an amphoteric oxide and evolves a neutral gas as the only gaseous product.
      1. ZnCO₃
      2. Pb(NO₃)₂
      3. NaNO₃
      4. PbO₂
      5. CuCO₃
   7. A substance which on heating leaves no residue in the test tube.
      1. (NH₄)₂Cr₂O₇
      2. NH₄CI
      3. Pb(NO₃)₂
      4. PbCO₃
      5. CuSO₄.5H₂O
   8. A hydrated efflorescent salt which undergoes a change in colour on heating.
      1. Na2CO₃.10H₂O
      2. CuSO₄.5H₂O
      3. Na₂SO₄.10H₂O
      4. MgSO₄.7H₂O
      5. Ca(NO₃)₂.4H₂O
   9. A coloured salt which on heating leaves behind a coloured residue, evolves a coloured gas, acidic to litmus and a colourless gas neutral to litmus.
      1. Zn(NO₃)₂
      2. Pb(NO₃)₂
      3. CuCO₃
      4. Cu(NO₃)₂
      5. (NH₄)₂Cr₂O₇
   10. A coloured salt which on heating leaves behind a coloured residue and evolves two gases one of which is unreactive at ordinary temperatures.
       1. NH₄CI
       2. Cu(NO₃)₂
       3. CuCO₃
       4. (NH₄)₂Cr₂O₇
       5. Pb₃O₄
   11. The gas evolved when iron [II] sulphide reacts with dilute sulphuric acid.
       1. CO₂
       2. NO₂
       3. H₂S
       4. SO₂
       5. SO₃
   12. The substance which reacts with dilute sulphuric acid evolving a neutral gas which burns with a characteristic 'pop' sound in air.
       1. Hg
       2. Ag
       3. Cu
       4. Pb
       5. Zn
   13. The substance which reacts with dilute sulphuric acid evolving a gas slightly acidic in nature and on application of the flame test imparts a golden yellow colour to the flame.
       1. NaNO₃
       2. Ca(NO₃)₂
       3. Na₂CO₃
       4. Na₂SO₃
       5. CaCI₂
   14. Water containing the following salt will not lather with ordinary soap after boiling and filtration.
       1. Ca(HCO₃)₂
       2. NaHCO₃
       3. CaSO₄
       4. Na₂SO₄
       5. Mg(HCO₃)₂
   15. A substance present in temporary hard water and which imparts a brick red flame on application of the flame test.
       1. CaCO₃
       2. Ca(NO₃)₂
       3. K₂SO₄
       4. Ca(HCO₃)₂
       5. NaHCO₃
   16. Hardness in water both temporary and permanent can be removed by addition of the following substance, followed by boiling and filtration.
       1. CaCO₃
       2. NaHCO₃
       3. Na₂CO₃
       4. MgCO₃
       5. Na₂SO₄
   17. Eutrophication is an increase in chemical nutrients in an ecosystem. It occurs in water bodies and is a source of pollution mainly due to increase in
       1. Ammonium salts
       2. Carbon dioxide
       3. Phosphates
       4. Sulphates
       5. Silicates
   18. Sodium sulphite reacts with dilute sulphuric acid to give a gas which
       1. Has no effect on lime water
       2. Turns acidified KMnO₄ soln. from clear colourless to pink
       3. Turns acidified K₂Cr₂O₇ soln. from orange to green
       4. Turns lead acetate paper silvery black
       5. Burns with a pop sound when burning splint is brought near it
2. 2.

   SELECT THE CORRECT ANSWER - for each of the following

   1. Reaction between two componds - base & acid - to give two new compounds - salt & water by interchange of radicals.
      1. Displacement
      2. Double decomposition
      3. Direct combination
   2. The insoluble salt obtained when a sample of temporary hand water is boiled is
      1. Copper carbonate
      2. Zine carbonate
      3. Magnesium carbonate
   3. During formation of an electrovalent compound - CaCI₂ - the calcium atom [⁴⁰₂₀Ca] loses electrons to attain stability of the nearest noble gas -
      1. Argon
      2. Neon
      3. Helium
   4. Relative molecular mass [RMM] of an element/compound compares the number of times, one molecule of the substance is heavier than 1/12th the mass of an atom of -
      1. Nitrogen
      2. Sulphur
      3. Carbon
   5. A colourless metallic oxide.
      1. Litharge
      2. Calcium oxide
      3. Copper [II] oxide
   6. A water soluble salt.
      1. Calcium bicarbonate
      2. Calcium carbonate
      3. Calcium sulphite
   7. A gas which is not a neutral gas.
      1. Carbon monoxide
      2. Nitric oxide
      3. Nitrogen dioxide
   8. A gas which when dissolved in water forms only one acid.
      1. Chlorine
      2. Sulphur dioxide
      3. Nitrogen dioxide
   9. The metal which displaces copper from copper [II] sulphate solution.
      1. Iron
      2. Silver
      3. Mercury
   10. The salt which undergoes a photochemical reaction.
       1. Lead bromide
       2. Copper [II] chloride
       3. Silver bromide
   11. A metal which reacts with steam forming an amphoteric oxide.
       1. Aluminium
       2. Iron
       3. Magnesium
   12. A gas which dissolves in water to give a weak acid.
       1. Sulphur dioxide
       2. Carbon dioxide
       3. Nitrogen dioxide
   13. A coloured efflorescent salt which leaves a white anhydrate residue.
       1. Copper [II] sulphate
       2. Glauber's salt
       3. Washing soda
   14. A subatomic particle with a positive charge.
       1. Proton
       2. Neutron
       3. Electron
   15. The valency of an element 'X' having atomic number = 19.
       1.  -1
       2. +1
       3. +2
   16. The chloride exhibiting covalent bonding.
       1. Sodium chloride
       2. Magnesium chloride
       3. Phosphorus trichloride
   17. The alkaline earth metal.
       1. Lithium
       2. Beryllium
       3. Potassium
   18. The halogen in the period containing the noble gas neon.
       1. Fluorine
       2. Chlorine
       3. Bromine
   19. The metal which does not liberate hydrogen on reaction with dilute acid.
       1. Iron
       2. Aluminium
       3. Lead
   20. An ammonium salt which on thermal decomposition leaves a coloured residue.
       1. Ammonium nitrate
       2. Ammonium chloride
       3. Ammonium dichromate
   21. The acid which reacts with calcium carbonate to give an insoluble salt.
       1. Dil. hydrochloric acid
       2. Dil. nitric acid
       3. Dil. sulphuric acid
   22. The gas obtained when calcium hydroxide reacts with ammonium chloride.
       1. Nitrogen
       2. Nitrogen dioxide
       3. Ammonia
   23. A coloured basic oxide.
       1. Lead [II] oxide
       2. Copper |I] oxide
       3. Zinc oxide
   24. A substance which reacts with dil. sulphuric acid to give a foul smelling acidic gas
       1. Sodium sulphite
       2. Sodium sulphide
       3. Sodium sulphate
   25. A salt which imparts a brick red flame during the flame test.
       1. Potassium chloride
       2. Sodium chloride
       3. Calcium chloride
   26. The conversion of 30 C to the Kelvin scale of temperature.
       1. 273 K
       2. 303 K
       3. 30 K
   27. V & T [at constant pressure] relates to the following Law.
       1. Boyles Law
       2. Charles Law
       3. Gas equation.
   28. The valency of nitrogen in the compound nitrogen monoxide [NO]
       1. +1
       2. +2
       3. +4
   29. The metal which shows a variable valency of +2 & +4.
       1. Copper
       2. Lead
       3. Silver
   30. The oxidized product in the reaction 2FeCl₃ + H₂S → 2FeCl₂ + 2HCI + S
       1. HCI
       2. FeCl₂
       3. S
   31. The substance which acts as a catalyst in the reaction H₂ + Cl₂ → 2HCI.
       1. MnO₂
       2. H₂O
       3. Iron
   32. The subatomic particle with a negative charge and negligible mass.
       1. Proton
       2. Electron
       3. Nucleon
   33. The most electronegative element.
       1. Nitrogen
       2. Fluorine
       3. Oxygen.
   34. The element in period 3 which is univalent and a good reducing agent.
       1. Chlorine
       2. Sodium
       3. Lithium
   35. The catalyst used in Bosch Process in the reduction of steam to hydrogen.
       1. Cr₂O₃
       2. FeO
       3. Fe₂O₃
   36. Acid rain affects the nutrients and fertility in the soil.
       1. Increases the above
       2. Decreases the above
       3. Increases nutrients but decreases fertility
   37. Ozone is formed by combination of.
       1. Oxygen with nascent oxygen atom
       2. Two nascent oxygen atoms & an oxygen molecule
       3. Two molecules of oxygen
3. 3.

   MATCH THE QUESTIONS IN LIST i - with their correct answers in List II.

   List I	List II
   1. CuSO4.5H2O	A: Deliquescent salt
   2. MgCI2	B: Hуgrоscopic
   3. P2O5	C: Efflorescent salt

    

4. 4.

   MATCH THE QUESTIONS IN LIST i - with their correct answers in List II.

   List I	List II
   1. P1 V1 - P2 V2 = K [T = constant]	A: Charle's law equation
   2. V1/T1 = V2/T2 = K [Pressure constant]	B: Gas equation
   3. P1V1/T1 = P2V2/T2 = K [constant]	C: Boyle's law equation

    

5. 5.

   MATCH THE QUESTIONS IN LIST i - with their correct answers in List II.

   List I	List II
   Conversion of
   1. Carbon dioxide to glucose	A: Electrochemical reaction
   2. Water to oxygen	B: Exothermic reaction
   3. Nitrogen to ammonia	C: Photochemical reaction

    

6. 6.

   MATCH THE QUESTIONS IN LIST I - with their correct answers in List II.

   List I	List II
   Covalent molecule
   1. Nitrogen	A: Two single covalent bonds
   2. Water	B: Four single covalent bonds
   3. Carbon tetrachloride	C: Triple covalent bond