ISC Chemistry Sample Paper for class 12

Oct 16 • Board Sample Papers • 9352 Views • 4 Comments on ISC Chemistry Sample Paper for class 12

Indian Certificate of Secondary Education (ICSE) is an examination conducted by the Council for the Indian School Certificate Examinations which is a private non-governmental board of school education in India for class XII. It has been designed to provide an examination in a course of general education in accordance with the recommendations of the New Education Policy 1986 (India)through the medium of English. This examination allows secure suitable representation of Governments responsible for schools (which are affiliated to it) in their States/Territories. The private candidates are not permitted to appear for this examination. So, here is a sample paper for the students to practice. i.e. Chemistry Sample Paper for class XII as per Indian Certificate of Secondary Education. In this section find the latest ICSE Chemistry sample paper for class 12 with questions from all the topics as per the syllabus. Still if it contains any error/mistakes  please do let us know using the comment sections. Any type of suggestions will be highly appreciated.

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 ICSE Chemistry Sample Paper for class 12

Full Marks : 70
Total Time : 3 Hrs

(a) Fill in the blanks by choosing the appropriate word/words from the given

(hydrolysis, reduction, oxidation, vacant, osmotic, above, benzic acid, phenol, aniline, below, can, decreases, increases, cannot, crystal, ionization, rate, rate constant.)

i. A catalyst _____________ start a reaction but itcan increase the _______________of the reaction.

ii. Electrons trapped in the _______________sites of the ______________lattice are called F-centres.

iii.An aqueous solution of sugar boils__________________ 100 degree Centigrade and freezes ____________ zero degree C.

iv. Toluene on __________________ with alkaline potassium permanganate gives _______________.

v. The degree of ___________________of ammonium hydroxide __________________on addition of ammonium chloride.

(b)(i) What is the equation for the action of heat on calcium nitrate ?

Ans- 2Ca(NO3)2———–> 2CaO + 4 NO2 + O2
2(40 + 28 + 96) 2(40+16) 4(14 + 32) 2(16)
(328g)—————-(112g)——184g——-32g
2 moles of Calcium nitrate produces 4 moles of NO2
1 mole calcium nitrate produces how many moles of NO2?
= 4/2 = 2 moles of NO2

(ii) What volume of O2 at STP will be produced on heating 65.6g of Ca(NO3)2?

Ans- 328g of Ca(NO3)2 produces 32g of O2
1g of Ca(NO3)2 produce how much of o2?
= 32/328
65.6g of Ca(NO3)2 produce how much of O2?
= 32/328 x 656/10 = 6.4g of oxygen
32g of O2 occupy 24 liters of volume
6.4g of O2 occupy how many liters?
= 22.4/32 x 64/10 = 4.48 liters.

(iii) Find out the mass of CaO formed when 65.6g of Ca(NO)3 is heated?

Ans- 328g of Ca(NO3)2 forms 112g of CaO
65.6g of Ca(NO3)2 produces how many grams of CaO?
= 112/328 x 656/10 = 22.4g of CaO

(iv) Find out the mass of CaO formed when 65.6g of Ca(NO3)2 is heated?

Ans- 5 moles of gaseous product is formed by 2 moles of Ca(NO3)2
1 mole of Ca(NO3)2 weighs = 164g
Then, 2 moles of Ca(NO3)2 weighs = 2 x 164 = 328g

(v) Find out the mass of calcium nitrate required to produce 44.8 liters of NO2 at S.T.P
(Relative molecular mass of Ca(NO3)2 = 164 and CaO = 56)

Ans- According to the given equation
4 x 22.4 liters of NO2 will be formed by 2 x 164g of calcium nitrate
44.8 liters of NO2 will be formed by how many grams of calcium nitrate?
NO2= 2 x 164/4 x 22.4 x 44.8 = 164g of calcium nitrate.
(Note: To do this type of lengthy sums you must have a clear understanding of basic concepts of the topic)

(c) Name the organic compound formed by each of the following reactions:

(i) CH3 COONa + NaOH ———-> (above the arrow Ca, below the arrow heat)
Ans. Methane

(ii) CaC2 + H2O——>
Ans. Acetylene (ethyne)

(iii) C2H5Br + KOH(alc.)—–>
Ans. Ethylene (ethene)

(iv) C2H5OH + CH3COOH——->
Ans. Ethyl alcohol (ethanol)

(v) C2H5OH +CH3COOH—–> (above the arrow conc.H2SO4 and below the arrow heat)
Ans. Ester (Ethyl acetate)

(d) Identify the following substances:

(i) An acidic gas which give dense white fumes with NH3

Ans. HCl gas

(ii) An alklane which can also be called a green house gas.

Ans. Methane (CH4)

(iii) A solid which can be kept in the open, forms a solution after sometime

Ans. Iron (III) chloride (a delequescence substance)

(iv) An alloy used in electrical fittings

Ans. Nickel steel

(v) A metal which gives hydrogen gas on reacting with both dilute acid and alkali

Ans. Zinc

(e) Write equations for the following reactions:

(i) Aluminium oxide and sodium hydroxide

Ans. Al2O3 + 2 NaOH ———–> 2NaAlO2 + H2O

(ii) Zinc and dilute sulphuric acid

Ans. Zn + H2SO4(dil.) ———-> ZnSO4 + H2

(iii) Nitrogen dioxide and water

Ans. 2NO2 + H2O———-> HNO3 + HNO2

(iv) Concentrated sulphuric acid and sugar

Ans. C12H22O11———–> 12C + 11 H2O (Above the arrow conc.H2SO4-dehydrating agent)

(v) Copper with concentrated nitric acid

Ans. Cu + 4HNO3———–> CU(NO3)2 + 2H2O + 2NO2

(f)Name the following:

(i) Second member of alkene series

Ans. Propene

(ii) First member of alkane series

Ans. Methane

(iii) Third member of aldehyde series

Ans. Propanal

(iv) Second member of carboxylic acid

Ans. Ethanoic acid

(v) Fourth member of alcohol series

Ans. Butanol

(g) Write IUPAC names of the following:

(i) Methanol
(ii) Propanone
(iii) Butan-2-ol
(iv) Ethoxyethane
(v) 2,2-dimethyl propane

Section II (40 Marks)
Question 2
(a) The following questions refer to periodic table:

(i) Name the second last element of periodic table
Ans. Chlorine

(ii) How many elements are in the second period?
Ans. Eight

(iii) Name the element which has the highest electron affinity
Ans. Chlorine

(iv) Name the element which has the highest electronegativity
Ans. Fluorine

(v) Name the metal which may be placed on group 1 but is not a metal
Ans. Hydrogen

(b) Fill in the blanks by using correct options:

(i) Metals have —– ionization potential.(low/high)

Ans. low

(ii) Group 18 elements have —— valence electrons (4/80 with the exception of —–(He/Ne) with —– electrons(2/8) in valence shell.

Ans. 8, He, 2

(iii) Group 2 elements are called —— metals (alkali/alkaline earth)

Ans. alkaline earth

Question 3
(a) Draw the different isomers having the following molecular formula:

(i) C5H12
Practice pentane isomers from text book.
(ii) C4H8(position)
Practice But-1-ene and But-2-ene diagrams from text book.

(b) What is denatured alcohol?

Ans. Denatured alcohol is prepared by adding substances like methyl alcohol or pyridine to ethyl alcohol. Denatured alcohol is poisonous due to the presence of methyl alcohol and it is undrinkable.

(c) Give two important uses of ethanol.

(i) It is a good solvent for resins and gums.
(ii) It is used in thermometers because of its low freezing point.
(iii) It is used in the manufacture of chemicals like dyes, perfumes, antiseptics etc.

(d) Write equations for:

(i) Preparation of ethanol by hydration of C2H4
Ans. C2H4 + H2O——-> C2H5OH (above arrow H+)

(ii) Preparation of acetic acid from ethanol
Ans. C2H5OH + O2———> CH3COOOH + H2O (above arrow 300 degrees celsius, below the arrow Pt.)

Question 4
(a) Name the method by which following compounds can be prepared: Select the appropriate method from the following list-Neutralization; direct combination; precipitation; metal+acid-use a method only once.

(i) Sodium sulphate

Ans. Neutralization

(ii) Silver chloride

Ans. Precipitation

(iii) Iron sulphide

Ans. Direct combination

(b) How will you distinguish between the following pairs of compounds using NH4OH

(i) Copper (II) sulphate and Iron (II) sulphate

Ans. By adding NH4OH to CuSO4, a pale blue ppt. of Cu(OH)2 is formed and it is insoluble in excess NH4OH and produce inky blue solution.

By adding NH4OH to CuSo4, a dirty green precipitate of Fe(OH)2 is formed and it is insoluble in excess of NH4OH.

(ii) Zinc nitrate and lead nitrate

Ans. By adding NH4OH to Zinc nitrate drop by drop, a white gelatinous ppt. is formed and it is soluble in excess of NH4OH.
By adding NH4OH to lead nitrate, a white ppt. is formed which is in soluble in excess of NH4OH.

(iii) Iron (II) sulphate and iron (III) sulphate

Ans. By adding NH4OH to FeSO4 solution, a dirty green ppt. of FeOH2 is formed which is insoluble in excess of NH4OH.
When NH4OH is added to FeSO4 solution, a reddish brown ppt. of FeOH3 is formed and it is insoluble in water.

(c) Name:

(i) A greenish yellow gas with pungent smell

Ans. Chlorine

(ii) An oxide which is yellow when hot and white when cold

Ans. Zinc oxide

(iii) A chemical used to deplete ozone layer

Ans. Chlorofluorocarbons

(iv) A crystalline salt without water of crystallization

Ans. Common salt- NaCl

Question 5
(a) Name one:

(i) metal liquid at room temperature

Ans. Mercury

(ii) non-metal which is a conductor of electricity

Ans. Graphite

(iii) neutral oxide

Ans. H2O

(iv) metallic oxide which cannot be reduced by hydrogen

Ans. Zinc oxide

(v) non-metal which has luster

Ans. Iodine

(b) (i) Name the chief ore of aluminum

Ans. Bauxite

(ii) Name the process used to concentrate the above mentioned ore.

Ans. Bayer’s process

(iii) Why alumina is added to cryolite in the electrolytic reduction of aluminum?

Ans. To reduce the fusion temperature from 2050 degrees celsius to 950 degrees celsius.

(iv) Give cathode and anode reactions involved in extraction of aluminum from its above mentioned ore.

Ans. Cathode: 4Al+3 + 12 e- ——-> 4 Al

Anode: 6O2- + 12e- ——-> 6(O)

3(O) + 3(O) ——–> 3O2

2C + 2O2 ——-> 2CO2

(v) Name the process used for the concentration of zinc blende

Ans. Froth floatation process
Question 6
(a) Draw a neat well labelled diagram for the silver plating on an iron spoon.

Practice the diagram from text book.

(b) Copy and complete the following table related to electrolysis.

Ans. 1. Product at cathode: Copper

Product at anode: Cu+2

2. Product at cathode: Lead

Product at anode: Bromine

(c) Classify the following as oxidation and reduction reaction, also complete the reaction.

(i) Cu——> Cu+2

Ans. Cu – 2e- —–> Cu+2 (oxidation)

(ii)Fe+3——–> Fe+2

Ans. Fe+3 + e- ——> Fe+2 (reduction)

(iii) Cl- ——-> Cl

Ans. Cl- – e- ——-> Cl (oxidation)

Question 7
(a) A compound has the following percentage composition by mass:
Carbon-54.55%, Hydrogen-9.09% and oxygen- 36.26%. Its vapor density is 44. Find the empirical formula and molecular formula of the compound.(H=1; C=12; O=16)

Ans.Carbon ——-4.55% ——12 ——–54.55/12 = 4.54— 4.54/2.26 = 2
Hydrogen ——- 9.09%——–1——–9.09/1 = 9.09—–9.09/2.26 = 4
Oxygen——-36.26%——–16——–36.26/16 = 2.26—–2.26/2.26 = 1
Empirical formula of the compound: C2 H4 O
Vapor density = 44
Molecular Mass = n = (VD x 2) 44 x 2 = n x 44
44 x 2 = n(44)
n = 2
Molecular formula = C4H8O2

(B) Give the electron dot structure of the following:

(i) NH3 (ii) CH4 (iii) H3O+
Draw and practice the pictures from text book.

(C) Compare the properties of covalent and electrovalent compounds on the following points.

Solubility:

Covalent: These compounds are insoluble in water and soluble in organic solvent.
Electrovalent: These compounds are soluble in water but insoluble in organic solvents.

Structure:

Covalent: Structure of covalent compounds are not much stable, usually they are amorphous solids or liquids.
Electrovalent: Structure is stable; usually crystalline solids.

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4 Responses to ISC Chemistry Sample Paper for class 12

  1. Sejal Chawhan says:

    Syllabus pattern

  2. Sejal Chawhan says:
  3. Isac says:

    why is only class 10 paper given after question a)

  4. Niyah says:

    I want a solved sample question paper for organic chemistry ISC XII th portions

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