Class 10 chemistry ICSE MODEL PAPER 2

Class 10  chemistry ICSE

MODEL PAPER 2

Class-X                                                                                                                                        Marks:80

Subject: Chemistry                                                                                                                   Time:2Hrs.

Answers to this paper must be written on the paper provided separately.

You will not be allowed to write during the first 15 minutes.

This time is to be spent on reading the Question Paper.

The time given at the head of this paper is the time allowed for writing the answers.

Section I is compulsory. Attempt any four questions from Section II. The intended marks for questions or parts of questions are given in brackets ( ).

Section I (40 Marks)

Answer all the questions

Question 1

a) Name the following.                                                                                                               5M

i)        The white precipitate, formed when a salt solution is treated with Silver nitrate solution, which dissolves in excess Ammonium hydroxide.

ii)      The substitution of a hydrogen atom from a Hydrocarbon by a Chlorine atom.

iii)    The separation of ions of an ionic compound when dissolved in water.

iv)    The salt formed by the partial replacement of Hydrogen ions by metal ions.

v)      The black metal oxide which liberates a greenish yellow gas when heated with concentrated HCl. 

b) Select the correct answers from A, B, C or D for the following statements.                          5M

i)   In Periodic table from left to right across a period the reducing property

A) increases                              B) decreases                   C) remains same       D) depends on

                                                                                                                          atomic number

ii)   A compound X consists of only molecules. X will have-

A)    Low M.P and B.P                                                                     B)  crystalline structure 

C) strong electrostatic force of attraction                      D) electrovalent bond

iii)    1 mole of Carbon dioxide (atomic weight of Carbon- 12)

A)    has 44 molecules                                                      B) occupies 22.4 ml      

C) 6.023x10²² atoms                                                      D) is equal to 44g of CO₂

iv)    The chemical added in the concentration of Bauxite ore.

A) Ammonium chloride                                                  B) Aluminium  hydroxide

C) Sodium hydroxide                                                      D) Cryolite

v)      A strong acid which is a strong oxidizing agent and does not produce Hydrogen with an active metal.

A) Sulphuric acid                     B) Hydrochloric acid        C) Carbonic acid   D) Nitric acid

c) Fill in the blanks:-                                                                                                                      5M           

i)        Molecules of __________ (Hydrogen/Nitrogen) contain triple bond.

ii)      In electrolysis the anions migrate towards ________ (anode/cathode) and they get ____________ (oxidized/reduced) to neutral atoms.

iii)    Dilute Nitric acid reacts with Copper to produce __________ (Nitric oxide/Nitrogen dioxide).

iv)    Ethyl bromide when boiled with ____________ (aqueous/alcoholic) Sodium hydroxide gives Ethene gas.

v)      By dissolving Alumina in Cryolite a ___________( condiucting/non-conducting) solution is produced.

d) Correct and rewrite the following statements.                                                                     5M    

i)        Addition of Sodium hydroxide to Alumina reduces its fusion point.

ii)      In Periodic table the number of shells remains same down a group.

iii)    Carbon tetra chloride is a non electrolyte because it contains free electrons.

iv)    Alkanes are more reactive than alkenes.

v)      Ammonia gas turns red litmus to blue.

e) Give reason why:                                                                                                                  5M

i) Solid Sodium chloride is a non electrolyte but in aqueous or fused state conducts electricity.

ii) Electrovalent compounds are non volatile.

iii) Ionisation potential decreases down a group.

iv) Zinc is added in the alloys like Bronze and Brass.

v) Cao is not used in the purification of Hydrogen chloride gas.

f) Name the gas produced in the following reactions and write the test for the gas in each case:  5M        

i) Conc.HCl is heated with red lead.

ii) Dilute HCl is added to Sodium sulphite.

iii) A dilute acid is added to a metal carbonate.

iv) Calcium carbide is treated with cold water.

v) Magnesium nitride is added to warm water.

g) Select the suitable word from the list given in brackets for each of the following statements.  5M        

        (Chlorine , Na₂O, NaHSO₄, Conc. Sulphuric acid, PbO, Fluorine, Basic salt)

i)        An acid salt

ii)      The salt formed by the partial neutralization of a base by an acid.

iii)    An amphoteric oxide.

iv)    The element with highest Electron affinity.

v)      A hygroscopic liquid substance.

h)          A) C + 2H₂SO₄ à CO₂+ 2SO₂ + 2H₂O    5M

         (at. wt. H-1, C-12, O-16, S-32)

Calculate:

i) The amount(mass) of Carbon and Sulphuric acid required to prepare 11.2 litres of Carbon dioxide .

ii) The number of moles of Sulphur dioxide released in the above case (i).

B) A gas of 32g occupies 20 litres of volume at STP. Then find its Relative Molecular Mass (Molecular weight).

C) Find the volume of Oxygen remains unused when a mixture of 450cc of Carbon monoxide and 300cc of Oxygen is ignited.

Section II (40 Marks)

Answer any four of the following questions

Question 2                                                                                                                             4+2+4

a)      The following elements belong to one group given in order from top to bottom.

Li, Na, K, Rb

i) Identify the element which has smallest atom among them.

ii) Which one of them can easily form a cation? Why?

iii) What is the common feature in their electronic configurations?

b)      Elements X,Y and Z with atomic numbers 15, 12, 17.

i) Which period do they belong to?

ii) Identify and arrange them in the increasing order of their non-metallic character.

c)      i) What is lone pair of electrons?

ii) State the nature of the bonds in Ammonium ion.

iii) Iron combines with a non-metal ‘X’, which contains molecules, to form a compound with formula FeX₃. Then write the balanced equation for the above reaction.

iv) Draw the electron structure of Hydronium ion.

Question 3                                                                                                                         2+3+3+2

a)      Give a suitable term for each of the following.

i) A definite number of water molecules bound to some salts.

ii) The process in which a substance absorbs moisture from the atmospheric air to become moist and ultimately dissolves in the absorbed water.

b)      A solution M turns blue litmus to red, so it must contain (i) ___________ ions, another solution turns red litmus to blue must contains (ii) __________ ions.

iii) Tetrammine Copper sulphate is a ___________ (normal/complex) salt.

c)      Write balanced equations for the following conversions:

i) CuCl₂ from CuCO₃

ii) Pb(NO₃)₂ to PbCl₂

iii) Preparation of Zinc sulphate by a simple displacement reaction.

d)      State your observations:

i) at cathode during electrolysis of Copper sulphate using Copper electrodes.

ii) at anode in electrolysis of fused Lead bromide.

Question 4                                                                                                                             4+4+2

a)      A, B and C are three water soluble compounds.

When their aqueous solutions are taken in the electrolytic cell and the key is on the following observations are seen.

.

If A is taken the bulb glows brightly, with B the bulb becomes dim but when C is taken the bulb does not glow.

Then choose the correct answer from A, B or C for the following statements.

i) The solution which contains molecules only.

ii) The solution which contains ions only.

iii) The solution which possesses ions and molecules. 

iv) If alcohol is taken in the electrolytic cell then state whether the bulb glows or not.

  

b)      i) Find the percentage of water in Magnesium nitrate crystals Mg(NO₃)₂.6H₂O

At. Wt. H-1, C-12, N-14, Mg- 24

ii) A compound contains C-14.4%, H-1.2% and Cl-84.5%. Determine the E.F and Molecular formula of the given compound. If V.D is 84. (At.wt H-1, C-12, Cl-35.5)

c)      i) State Gay Lussac’s Law.

ii) Metals are ________________ (electropositive /electronegative) in nature.

Question 5                                                                                                                                3+4+3

a) i) Which property of Bauxite makes it react with Sodium hydroxide.

ii) Name the alloy of Zinc and Copper.

iii) State the function of Aluminium in Thermite process.

b) i) Compare the properties of metals and non metals in terms of

A) Electronic configuration         B) Oxidizing property

ii) Write balanced cathode reaction in the electrolysis of fused Alumina.

iii) Name the material coated on the inner surface of the steel tank in the above process (ii).

c) i) Give balanced equation for the lab preparation of HCl gas.

   ii) State any one precaution in the above process (i).

   iii) Write balanced equation for the reaction between dilute HCl and Sodium thiosulphate.

Question 6                                                                                                                            3+2+2+3

a)      State your observations in the following cases:

i) Catalytic oxidation of Ammonia in excess Oxygen.

ii) Reduction of Copper oxide using Ammonia gas.

iii) Conc. HNO₃ is heated with Copper turnings. 

b)      State the catalyst and conditions maintained in Haber’s process.

c)      Give reason :

i) All glass apparatus is used in the lab preparation of Nitric acid.

ii) 90% of all known compounds are organic in nature.

d)     i) Give IUPAC names       

ii) Draw the branched structure of Ethanoic acid.

Question 7                                                                                                                               2+2+3+3

a)      Write balanced equations for the following reactions:

i) Reaction between 1,2-dibromo Ethane and alc.KOH on boiling.

ii) Ethanol with Conc. H₂SO₄ at 170⁰C

b)      Name the following:

i) Catalyst used in the conversion of Ethene to Ethane.

ii) The reaction between Ethyl alcohol and Acdetic acid in presence of Conc.sulphuric acid.

c)      Identify the anion present in the compounds X, Y and Z

i) A compound X reacts with BaCl₂  solution to give white precipitate which is insoluble in dil. HCl.

ii) A compound Y on heating with conc. Sulphuric acid and Copper turnings gives reddish brown vapours which give violet vapours with Potassium iodide.

iii) A compound Z on adding conc. Sulphuric acid gives a colourless gas which gives a white precipitate with Silver nitrate solution that dissolves in Ammonium hydroxide.

d) Name the cations present in each of the following when NH₄OH added.

i) A salt P gives a pale blue precipitate which turns to inky blue solution.

ii) A salt solution B gives dirty green precipitate.

iii) A salt R gives no precipitate with Ammonium hydroxide but gives a white ppt. with Sodium hydroxide.