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SECTION - I (40 marks)Compulsory : Attempt all questions from this section.

Question 1.(a) Identify the Following : (Molecular formula not acceptable)(i) A Dipole molecule(ii) Compound Used for the preservation of fruits(iii) A salt which is a strong electrolyte(iv) Gas produced on reaction of dilute sulphuric acid with a metallic sulphide.(v) Alloy used in Beam balance

(b) Given below are certain acids, match them with the specifications whichbest describes the classifications of the acids :H3PO4, HI, H3CCOOH, H2CO3, HNO3

(i) A strong acid(ii) An Oxy- acid(iii) A Hydra - acid(iv) An Organic acid

(c) Write balanced equation for each of the following cases :(i) Thermal dissociation of Hydrogen Chloride gas(ii) Solid Ammonium chloride is warmed with slaked lime(iii) Aluminium nitride is treated with warm water(iv) Ammonia reacts with lead oxide(v) Acetic acid reacts with magnesium

(d) Identify the following A,B,C,D and E in each case based on the informationgiven below :

(i) An efflorescent substance A which when exposed to dry air becomes amonohydrate.

(ii) A Yellow coloured compound B when treated with caustic soda forms a reddishbrown precipitate.

(iii) A Compound C on undergoing electrolysis gives dark reddish brown fumes atthe anode.

(iv) An element D which is refined by Electrolysis(v) A dilute acid E which on warming with metallic nitrites gives metallic chlorides

and Oxides of non metals.

(e) Give the Structural formula of the following :(i) Isopentane(ii) Butylene(iii) 1- Butanol(iv) Formic acid(v) Propene

(f) Give the formation of the following electrovalent compounds :(1) Electron dot diagram and Molecular structure of MgCl2, NaCl and CaO.

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MC 17 C - 9

MT EDUCARE LTD. X - ICSE (Chemistry)

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(g) The compound A has the following % composition by mass :C = 26.7 %, O = 71.1 % , H = 2.2%. Determine the empirical formula If therelative molecular mass of A is 90, what is the molecular formula of A?[H = 1, C = 12, O = 16]

SECTION - II(Attempt any four questions)

Question 2.(a) Arrange the Following elements as directed :(i) Ar, He, Ne, (In increasing order of number of electron shells)(ii) Li, F, C, O ( In increasing Order of electron affinity)(iii) Cl, Mg, P, Na,( In increasing Order of atomic size)(iv) Cl, Li, F, N ( In increasing Order of electronegativity)(v) Cl, S, Al, Na (In increasing Order of ionization potential)

(b) Correct the following statements and rewrite :(i) Calamine is a Common ore of Iron(ii) Chlorine is a bleaching agent(iii) Dry ammonia is a weak base(iv) Lead bromide conducts electricity(v) Volume of a given mass of gas is directly proportional to its absolute

temperature, if pressure is kept constant.

Question 3.(a) A metal article is to be electroplated with silver. The electrolyte selected is

Sodium argentocyanide.(i) Why is Sodium argentocyanide preferred over silver nitrate.(ii) The ions not discharged in the electrolytic process is / are ___________.(iii) Write the reaction taking place at the Cathode.(iv) Write the reaction taking place at the anode.(v) Give the dissociation reaction of the electrolyte.

(b) Complete the following table and Rewrite :

Question 4.Given below are questions based on the Laboratory preparation of Ammoniafrom ammonium chloride.

(i) Give the reactants used in the Process. (molecular formula expected)(ii) Write the reaction of the preparation process.(iii) What is the drying agent used ?(iv) How is the gas collected? Justify(v) Specify One precaution to be taken(vi) NH4NO3 is not used in the preparation because ______________.(vii) Compare giving two points the Preparation of NH3 from AlN and NH4Cl

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Use of the element/compound

Purify bone black

Smelling salt

Preparation of iodine

Making of polyethene

Solvent for resins

Element/compound

MC 17 C - 9

MT EDUCARE LTD.X - ICSE (Chemistry)

264

Question 5.(a) An Organic compound has oxygen 26.24% and hydrogen 4.92%. Find its

empirical formula.

(b) Find the Percentage of water of crystallization in Blue Vitriol.(Atomic mass of S-32, Cu-63.5, O-16, H-1)

Question 6.(a) Define the Following :(i) Mole(ii) Ionization potential(iii) Deliquescence(iv) Co-ordinate bond(v) Electronegativity

(b) Fill in the blanks and rewrite the complete statement :Ionic bonds are formed by __________ of electrons. They exist in __________ state.Melting and boiling points of ionic compounds are __________ than covalentcompounds. The general formula of Alkanes is __________ and that of Alkenesis __________.

Question 7.(a) Give the chemical reaction for :(i) Dehydrohalogenation of Ethyl chloride.(ii) Preparation of ethyne from 1,2 - dibromoethane(iii) Industrial preparation of ethanol by hydration(iv) Reaction of ethyne with iodine.(v) Formation of ethene by Dehydration with conc. Sulphuric acid

(b) State the conditions for the following :(i) Formation of acetaldehyde from acetylene(ii) Formation of nitric oxide from ammonia.(iii) HCl formed from NaHSO4(iv) Formation of ammonia from NH4Cl(v) Yellow lead monoxide is reduced to greyish white metal.

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