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ICSE Class X Board Examination

ICSE Chemistry (Science Paper 2) — Board Examination 2025

Board2025Subject code 522
Open source paper at oswaal360.com (opens in a new tab)
Board
ICSE Class X Board Examination
Class
Class 10
Subject
Chemistry
Year
2025
Total marks
Not verified
Duration
Not verified

Verification and rights

Follows the published ICSE syllabus structure and links back to the source, but has not been reconciled line by line against a Council document.

Imported board paper from Oswaal Books (reproduction of CISCE board paper) on 2026-08-29.

Questions in this paper

  1. 2((i))Column A Column B a. N2 + 3H2  2NH3 1. Vanadium
    A student was instructed by the teacher to prepare Pentoxide
    and collect ammonia gas in the laboratory by
    b. 4NH3 + 5O2 → 4NO + 2. Nickel
    using aluminium nitride. The student had set up
    6H2O
    the apparatus as shown in the diagram below.
    Study the given diagram and answer the following c. 2SO2 + O2  2SO3 3. Iron
    questions: d. C2H4 + H2 → C2H6 4. Concentrated
    X Ammonia gas Sulphuric acid
    e. CuSO4.5H2O → CuSO4 5. Platinum
    + 5H2O
    Y (v) (a) Draw the structural diagram for the following
    Aluminium organic compounds:
    nitride Water 1. 2-methyl propene 2. butanal
    (b) Give IUPAC name for the following organic 3. H
    compounds: |
    1. Cl Cl H — C — H H H
    | | | | |
    H—C—C—H C=C — C — C — H
    | | | | | |
    Cl Cl H H H H
    H H H
    O
    2. H C C C C
    O—H
    H H H
    SECTION – B (40 Marks)
    (Attempt any four questions from this Section)
    Question-3 (iii) Name the gas produced during each of the following    5 marks
  2. 2((i) [cont.])Column A Column B a. N2 + 3H2  2NH3 1. Vanadium
    The atomic number of two atoms 'X' and 'Y' are 14 reactions:
    and 8 respectively: (a) When copper is treated with hot, concentrated
    State nitric acid.
    (a) the period to which 'X' belongs. (b) When ammonia is burnt in an atmosphere of
    (b) the formula of the compound formed between oxygen.
    'X' and 'Y'. (c) When ferrous sulphide reacts with dilute
    (Do not identify X and Y) hydrochloric acid.    3 marks
  3. 2((ii))Column A Column B a. N2 + 3H2  2NH3 1. Vanadium
    Justify the following statements: (iv) Study the table given below. Use only the letters
    (a) Anode is known as the oxidising electrode. given in the table to answer the questions. Do not
    (b) Graphite electrodes are preferred in the identify the elements.
    electrolysis of molten lead bromide. IA IIA IIIA IVA VA VIA VIIA 0    3 marks
  4. 2((iii))Column A Column B a. N2 + 3H2  2NH3 1. Vanadium
    The reaction between concentrated sulphuric acid
    E J Q
    and magnesium can be represented by the equation
    given below: L G
    Mg + 2H2SO4 ® MgSO4 + 2H2O + SO2 M D P
    If 60 g of magnesium is used in the reaction, N
    calculate the following: (a) State the valency of element 'G'.
    (a) The mass of sulphuric acid needed for the (b) Which element can exhibit catenation?
    reaction. (c) Write the formula of the compound formed
    (b) The volume of sulphur dioxide gas liberated at between 'M' and 'P'.
    S.T.P.
    [Atomic weight: Mg=24, H=1, S=32, O=16] Question 5
  5. 2((iv))Column A Column B a. N2 + 3H2  2NH3 1. Vanadium
    Give one significant observation when: (i) Given below are two sets of elements from two
    (a) a solution of barium chloride is added to zinc different periods.
    sulphate solution. Name the element with the highest ionisation
    (b) lead nitrate is heated in a test tube. potential in each of the following sets.
    (c) chlorine gas is passed over moist starch iodide (a) Al, Cl, Mg
    paper. (b) Ne, O, F    2 marks
  6. 4((i))(ii) Ammonia gas is passed over heated copper (II)
    A gas cylinder can hold 150 g of hydrogen under oxide in a combustion tube:
    certain conditions of temperature and pressure. If (a) Name the gas evolved
    an identical cylinder with the same capacity can (b) What will be the colour of the residue that is
    hold 450 g of gas 'G' under the same conditions of left in the combustion tube at the end of the
    temperature and pressure, find: reaction?
    (a) the vapour density of the gas 'G'. (iii) Give balanced equations for the following:
    (b) the molecular weight of gas 'G'. (a) Action of dilute hydrochloric acid on ammonium    2 marks
  7. 4((ii))(ii) Ammonia gas is passed over heated copper (II)
    Complete and balance the following equations: carbonate.
    (a) CH3COONa + NaOH Cao
     → (b) Oxidation of sulphur with hot concentrated
    ∆
    nitric acid.
    (b) CH3COOH + Mg ® (c) Reaction of concentrated sulphuric acid with
    carbon.
  8. 4((iv))(ii) Ammonia gas is passed over heated copper (II)
    Rohit took two different salt solutions in test (D) H H H H
    tubes C and D as shown in the figure below. He | | | |
    added dilute HCl to each of the two test tubes. The H — C — C — C — C — H
    products formed in the test tubes C and D are silver | | | |
    chloride and lead chloride respectively. H H H H
    (E) H H
    | |
    H— C—C—H
    | |
    dilute dilute H H
    HCl HCl (F) H H H
    | | |
    H — C — C — C — H
    | | |
    Pb(NO3)2
    AgNO3 H | H
    solution solution H—C— H
    Test Test |
    State: H
    (a) One common observation made by Rohit in (a) Which compound forms a single product with
    both the reactions. bromine?
    (b) The observations made by him on addition of (b) Which two compounds have the same molecular
    excess of ammonium hydroxide to the products formula?
    formed in: (c) Which two compounds will react together in the
    1. test tube C present of concentrated H2SO4 to form a product
    2. test tube D with a fruity smell?
  9. 6((i))(iii) An organic compound 'X' contains carbon, oxygen and hydrogen only. The percentage of carbon and
    Given below is a diagram showing the placement hydrogen are 47.4% and 10.5% respectively. The
    of five different oxides. With respect to the given relative molecular mass of 'X' is 76. Find the empirical
    diagram answer the following questions: formula and the molecular formula of 'X'.
    [Atomic weight: C=12, O=16, H=1]
    Na2O CuO Question 7
    ZnO
    SO2 (i) Seema added a few pieces of copper turnings to a
    Fe2O3 test tube containing concentrated acid P and she
    noticed that a reddish-brown gas evolved.
    (a) Name the acid P used by Seema.
    Basic Acidic
    Region X (b) write a balanced chemical equation for the
    oxides oxides reaction that took place.
    (a) Name the type of oxide represented in region X (ii) Answer the following questions with reference to
    in the diagram. the concentration of bauxite ore.
    (b) Identify the oxide which has been incorrectly (a) Name the process used to concentrate the ore.
    placed in the above diagram. (b) Give a balanced chemical equation for the
    (c) Name the oxide from the above diagram which conversion of aluminium hydroxide to pure
    will form an alkali when dissolved in water. alumina.    4 marks
  10. 6((ii))(iii) An organic compound 'X' contains carbon, oxygen and hydrogen only. The percentage of carbon and
    Given below are organic compounds labelled A to F. (iii) Draw the dot and cross structure of the following:
    Answer the questions that follow:
    H (a) An ionic compound formed when Mg reacts
    O—H with the dilute HCl.
    (A) H C C (b) A covalent compound formed when H2 reacts
    O with Cl2.
    H
    (c) The positive ion produced when ammoia gas is
    H H
    dissolved in water.
    (B) H C C O [Atomic number: Mg=12, Cl=17, H=1, N=7]
    H (iv) Acidulated water is electrolysed using platinum
    H H
    electrodes.
    H H
    (C) C=C Answer the following questions:
    H H (a) Why is dilute sulphuric acid added to water?
    (b) Write the reaction taking place at the cathode.
    (c) What is the observation at the anode?    3 marks
  11. 8((i))(a) A colourless gas which turns acidified K2Cr2O7 from orange to green.
    (a) State Avogadro's Law.
    (b) A yellow explosive oily liquid formed when
    (b) Define Co-ordinate bond. excess chlorine gas reacts with ammonia gas.
  12. 8((ii))(a) A colourless gas which turns acidified K2Cr2O7 from orange to green.
    Differentiate between the following pairs of (c) A yellow metallic oxide formed on thermal
    compounds using the reagent given in the bracket: decomposition of PbCO3.    2 marks
  13. 8((iv))(a) A colourless gas which turns acidified K2Cr2O7 from orange to green.
    P, Q, R and S are the different methods of preparation
    (a) Ammonium chloride and sodium chloride (using of salts.
    an alkali)
    P - Simple displacement
    (b) Zinc nitrate solution and calcium nitrate solution
    (using excess sodium hydroxide solution) Q - Neutralisation by titration    3 marks
  14. 8((iii))(a) A colourless gas which turns acidified K2Cr2O7 from orange to green.
    You are provided with some compounds in the box. R - Precipitation
    S - Direct combination
    PbO CH4 PbO2 CO2 Choose the most appropriate method to prepare the
    HCl NCl3 SO2 following salts:
    (A) PbCl2
    (B) FeCl3
    Choose the most appropriate compound which fits (C) Na2SO4
    the descriptions (a) to (c) given below:
    qqq    3 marks