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

Question 1.(a) Name the following:(i) A gas which turns lead acetate paper black.(ii) A gas which turns Nessler’s reagent brown.(iii) An acid that can form two different Sodium salts.(iv) A nitrate made of only non metals.(v) A compound formed when Acetic acid reacts with Ethyl alcohol.

(b) What will you observe when:(i) A piece of Zinc metal is added to the solution of Copper sulphate taken in a test

tube.(ii) Nitric acid is stored in a reagent bottle in the laboratory over a period of time.(iii) Dil. Sulphuric acid reacts with Sodium sulphide.(iv) Manganese dioxide is heated with conc. Hydrochloric acid.(v) Ammonia is passed over heated Copper oxide.

(c) Solve the following:(i) Which has greater percentage of Oxygen - Calcium carbonate or Calcium nitrate.

[Ca = 40, O = 16, S = 32, C = 12, N = 14](ii) 80cm3 of Methane is mixed with 200cm3 of pure Oxygen at room temperature

and pressure. The mixture is then ignited when it burns as illustrated below,Calculate the composition of the resulting mixture. CH4 + 2O2 CO2 + 2H2O.

(d) Write the balanced chemical equations for the following reactions:(i) Reaction of ammonia with excess chlorine.(ii) Dehydration of oxalic acid by conc. Sulphuric acid(iii) Reaction of cold dilute Nitric acid with Copper.(iv) Addition of Hydrogen iodide to a test tube containing Conc. Sulphuric acid.(v) Reaction of Lead dioxide with Conc. Hydrochloric acid.

(e) Answer the following:(i) When Ammonium salt is warmed with Sodium hydroxide solution, a gas is

evolved State one chemical test by which you can identify this gas.(ii) Write a balanced chemical equation for the reaction of Lead with Caustic soda.(iii) Sodium hydroxide is added to solution X. A dense white precipitate is formed

which is soluble in excess of NH4OH. Identify the metal ion present in solution X.(iv) Give reason : Sodium hydroxide is used in the identification of cations.

(f) (i) Write the IUPAC name of :(i) Acetic acid 2) Acetylene

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(ii) Draw branched structural formulae of the following.(1) 3, 3 –dibromo – 1– butanal(2) 3-Methyl –2–Pentene(3) Methoxy methane

(g) (i) When a green solid P was heated. It turns into black solid Q and a colourlessgas X was given off. On passing gas X over heated carbon, another colourlessgas Y formed. Gas Y burns in oxygen to reform gas X.

a) Identify gases X and Y.b) How will you test gas X?c) Identify P.

(ii) The table below shows the results of heating the carbonates and nitrates tothe same temperature.

Arrange these metals in the increasing order of reactivity.

(h) (i) The atomic numbers of two elements X and Y are 12 and 17 respectively.1. Write the formula of the compound formed between X and Y.2. What type of particles constitute the compound formed between X and

Y?3. State whether the compound of X and Y will dissolue in Water or in

Carbon tetrachloride?

(ii) Electronegativity increases across a period from left to right. Give reason.

SECTION - II(Attempt any four questions)

Question 2.(a) The elements T and V are in the same period of the periodic table. T forms

ions by loss of electrons and V forms ions by gain of electrons.(i) Write chemical equations to show how T and V form ions, if the valency of T is 3

and V is 2.(ii) If T belongs to the 3rd period, what will be the nature of oxide formed?

(b) The type of reaction between Ethene and Chlorine is different from thatbetween Ethane and Chlorine.

(i) What is the type of reaction between Ethene and Chlorine?(ii) What feature of Ethene structure makes such a reaction possible?(iii) Write balanced chemical equation for (i) ?

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Metal Products of decomposition

Metal carbonate Metal Nitrate

M No change Metal nitrite and Oxygen

N Oxide and Carbon dioxide Metal oxide, nitrogen dioxide, oxygen

L Carbon dioxide, metal and Metal, nitrogen dioxide and oxygen Oxygen

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(c) How will you bring about the following conversions?[Give balance chemical equation to support your answer]

(i) Ethane to Acetaldehyde(ii) Methane to Ethyne(iii) Ethanol to Diethyl ether(vi) Ethyne to Ethene

Question 3.(a) Draw electron dot diagram for the formation of Ammonium ion.

(b) Name the following:(i) Two covalent compounds which do not conduct electricity in gaseous state

but when dissolved in water conduct electricity.(ii) The electrode of an electrolytic cell where reduction takes place.

(c) Distinguish between the following: (Any two points)(i) Polar covalent compounds and Non polar covalent compounds(ii) Strong electrolytes and Weak electrolytes

Question 4.(a) The extraction of Zinc from Zinc blende involves two chemical reactions. Write

balanced chemical equations for these reactions.

(b) A gaseous hydrocarbon of weight 0.70g, contains 0.10g of hydrogen. If thevapour density of the hydrocarbon is 35, find :(i) Its molecular formula.(ii) Write its structural formula. [C = 12, H =1]

(c) The following questions are based on the electroplating of Silver:(i) Name the electrolyte used.(ii) State why the above compound is preferred over Silver nitrate as an

electrolyte?

Question 5.(a) What amount of dil. Sulphuric acid will be required to dissolve 3g Magnesium

carbonate? [Mg = 24, C = 12, S = 32, O = 16]MgCO3 + H2SO4 MgSO4 + H2O + CO2

(b) The following questions are based on the pH of solutions.(a) 1(b) 4(c) 7(d) 10Choose from a to d the pH of:(i) A weakly acidic solution(ii) A non electrolyte(iii) A strongly acidic solution(iv) A electrolyte

(c) State the method used for the laboratory preparation of the following salts:(i) Ammonium sulphate(ii) Calcium carbonate(iii) Lead nitrate(iv) Zinc sulphate

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Question 6.(a) How will you distinguish between Calcium sulphate and Zinc sulphate using

only one laboratory reagent?

(b) B is a Sodium salt. When solution of B was added to aqueous Silver nitrate, awhite precipitate C was formed. The precipitates did not dissolve in dilute nitricacid. Identify the anion in B and the white precipitate C.

(c) Write balanced chemical equations for the following conversions.(i) Iron to Iron (II) chloride(ii) Ammonium chloride to Ammonia(iii) Copper metal to Copper sulphate(iv) Phosphorous to Phosphoric acid

(d) Give reason: Sulphuric acid is diluted by addition of acid to water.

Question 7.(a) Among the metals, Aluminium, Iron, Zinc, Copper. Name the following :

(DO not repeat the answer)(i) The metal that forms coloured ions.(ii) The metal that can be obtained form its ore by electrolysis.(iii) One metals that can form oxides that can be reduced by carbon monoxide.(iv) One metal that does not displace Hydrogen from dilute acids.

(b) Arrange the following elements as per the guidelines in the brackets.(i) Cl, Mg, Na, P [Increasing order of atomic size](ii) C, F, Li, O [increasing order of electron affinity](iii) Ar, He, Ne, Kr [decreasing order of number of electronic shells]

(c) Ethene and Ethane are both hydrocarbons.(i) Name one substance which will react with Ethene but not with Ethane.(ii) Write one chemical test to identify the gases.(iii) Name a polymer formed from one of the gases.

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