Past year question papers of ICSE Class X Chemistry Exam

Can you please give me the past year question papers of ICSE Class X Chemistry Exam
As it is very urgent for me?

As you want to get the past year question papers of ICSE Class X Chemistry Exam so here is the information of the same for you:

SECTION I (40 Marks)
Attempt all questions from this Section
Question 1
(a) Chlorine is subject of the following questions: [5]
i. What is the atomicity of chlorine?
ii. Name the compounds formed when chlorine reacts with water (formulae are NOT
acceptable.)

iii. Chlorine reacts with white phosphorous forming phosphorous trichloride and
phosphorous pentachloride. Write balanced equations for the formation of each of
these compounds.
(b) Answer the following questions, relating your answers only to salts in the list given
below:
Anhydrous calcium chloride, copper sulphate-5-water, sodium carbonate-10- water. [5]

i. Which compound is efflorescent?
ii. Which compound is blue in colour?
iii. Which compound is deliquescent?
iv. What would be seen on mixing a solution of calcium chloride with a solution of
sodium carbonate?
v. Write the balanced equation for the reaction occurring when a solution of calcium
chloride is mixed with a solution of sodium carbonate.
(c) In this question you are required to supply the word (or words) that will make each
sentence into correct statement which is to be written down in full.

Example : Sodium reacts with chlorine to form sodium chloride. Molten sodium reacts
with chlorine to form sodium chloride [5]
i. The electrolysis of lead bromide liberates lead and bromine.
ii. Copper sulphate crystals are dehydrated by sulphuric acid.
iii. Calcium nitrate reacts with sodium sulphate to form calcium sulphate (same is
required in two places).
iv. Crystals of sulphur are obtained when a solution of sulphur in carbon disulphide
is allowed to evaporate.
(d) If a crop of wheat removes 20 kg of nitrogen per hectare of soil, what mass of the
fertilizer, calcium nitrate Ca(NO3)2 would be required to replace nitrogen in 10 hectare
field? (N = 14, O = 16, Ca = 40), (Answer to nearest kg.) [5]
(e) [5]

i. A vessel contains N molecules of oxygen at a certain temperature and pressure.
How many molecules of sulphur dioxide can the vessel, accommodate at the same
temperature and pressure?
ii. Each of two flasks contain 2.0 g of gas at the same temperature and pressure. One
flask contains oxygen and the other hydrogen.
a. Which sample contains the greater number of molecules?
b. If the hydrogen sample contains N molecules, how many molecules are present
in oxygen sample?
iii. A gas sample occupies 4 litre at 27°C and P atmospheric pressure. What would be
its volume at 327°C and 2P atmospheric pressure?
(f) Describe in each case one chemical test that would enable you to distinguish between
the following pairs of chemicals. Describe what happens with each chemical or state no
'visible reaction'. [9]

i. Sodium chloride solution and sodium nitrate solution.
ii. Sodium sulphate solution and sodium chloride solution.
iii. Calcium nitrate solution and zinc nitrate solution.
(g) Write balanced equations for each of the following reactions: [6]
i. Magnesium heated in nitrogen.
ii. Action of heat on sodium nitrate.
iii. Action of heat on copper nitrate.
iv. Zinc and dilute sulphuric acid.
v. Ethene and hydrogen.
vi. Nitrogen monoxide and oxygen.

SECTION II (40 marks)
Attempt any four questions

Question 2
(a) Choose the correct word or phrase from the brackets to complete the following
sentences: [4]
i. Ammonium chloride is a soluble salt prepared by ................ (precipitation,
neutralisation).
ii. When ammonium chloride is heated, it undergoes ................ (thermal
decomposition, thermal dissociation).
iii. Heating ammonium chloride with sodium hydroxide produces ................
(ammonia, nitrogen).
iv. Heating a solution of ammonium chloride and sodium nitrite produces
................... (ammonia, nitrogen)
(b) Write correctly the balanced equation for each of the reactions mentioned in statement
(i) to (iv) above. [4]
(c) Describe what you see when concentrated nitric acid is added to copper. [2]

Question 3
(a) [5]
i. What is the colour of the flame when sulphur burns in air?
ii. Name the product formed when sulphur is burnt in air or oxygen.
iii. When burning sulphur reacts with water, a compound is formed. Name the
compound.
iv. Write the balanced equation for the reaction between sulphur dioxide and moist
chlorine.
v. In the reaction mentioned in question (iv) above, which substance is the oxidising
agent?
(b) [3]
i. What is the purpose of the contact process
ii. Name the catalyst used in the contact process.
iii. Write the balanced equation for the reaction in the contact process which takes
place in the presence of the catalyst.
(c) [2]
i. When hydrogen sulphide reacts with oxidising agent, what substance is always a
product of the reaction?
ii. What is the colour of the precipitate formed when hydrogen sulphide is bubbled
through copper sulphate solution?

Question 4 [2]
(a) With reference to the reduction of copper oxide, iron (II) oxide, lead (II) oxide and
magnesium oxide by hydrogen, place the oxides in order of increasing case of reduction.
That is, put first the oxide that is most difficult to reduce, and last, the oxide that is most
easily reduced.
(b) Write balanced equation for the following reactions: [3]
i. Reduction of copper oxide by hydrogen.
ii. Reduction of iron (III) oxide by carbon monoxide.
iii. Reduction of lead (II) oxide by carbon.
(c) [3]
i. What is the type of bonding expected in metallic chloride?
ii. If fused metallic chloride is electrolysed, at which electrode would the metal be
obtained?
iii. What metallic property is shown by the non-metal graphite?
(d) [2]
i. Cast iron contains about 4% carbon. By what chemical process is the amount of
carbon decreased to make steel?
ii. Which metal is added to steel to make stainless steel?

Question 5
(a) Concentrated nitric acid oxidises phosphorus to phosphoric acid according to the
following equation:
P + 5HNO3 ——-> H3PO4 + H2O + 5NO2 [8]
i. What mass of phosphoric acid can be prepared from 6.2 g of phosphorus?
ii. What mass of nitric acid will be consumed at the same time?
iii. What would be the volume of steam at the same time of measured at 760 mm Hg
pressure and 273°C?
(H = 1, N = 14; O = 16; P = 31)
(b) Ammonia may be oxidised to nitrogen monoxide in the presence of a catalyst
according to the following equation:
4NH3 + 5O2 ——> 4NO + 6H2O
If 27 litres of reactants are consumed, what volume of nitrogen monoxide is produced at
the same temperature and pressure ? [2]

Question 6 [6]
(a) For each of the compounds: (i) Ethane, (ii) Vinegar, (iii) Marsh gas, draw the relevant
structural formula.
(b) [4]
i. What word is used to describe these three compounds taken together?
ii. What is the special feature of the structure of:
(1) C2H4 (2) C2H2
iii. What type of reaction is common to both of these compounds?

Question 7
(a) Define the following terms: [3]
i. Acid
ii. pH scale
iii. Neutralisation.
(b) [7]
i. Outline the steps that would be necessary to convert insoluble lead (II) oxide into
insoluble lead chloride.
ii. Write the balanced equations for the reactions required to convert insoluble lead
(II) oxide into insoluble lead chloride.
iii. If iron reacts with dilute sulphuric acid, what will be the products?
iv. A solution of iron (III) chloride has a pH less than 7. Is the solution acidic or
alkaline?

SECTION I (40 Marks)
Attempt all questions from this Section
Question 1
(a) Name (formula is not acceptable) the gas produced in each of the
following reactions:- [5]
i. Action of concentrated nitric acid on copper.
ii. Exposure of chlorine water to sunlight.
iii. Burning of sulphur.
iv. Heating of ammonium nitrate (name only the nitrogen containing
compound)
v. Warming ammonium sulphate with sodium hydroxide solution.
(b) State what do you observe when:- [5]
i. Neutral litmus solution is added to an alkaline solution.
ii. Ammonium hydroxide is added to iron (III) sulphate solution.
iii. Lead nitrate solution and sodium chloride solution are mixed.
iv. Ethene is bubbled through a solution of bromine in
tetrachloromethane (carbon tetrachloride).
v. Sulphur burns.
(c) [5]
i. When gases react together, their reaction volume bears a simple ratio
to each other under the same conditions of temperature and pressure.
Who proposed this gas law?
ii. What volume of oxygen would be required for the complete
combustion of 100 litres of ethane according to the following
equation?
2C2H6 + 7O2 → 4CO2 + 6H2O

iii. The gases chlorine, nitrogen, ammonia and sulphur dioxide are collected
under the same conditions of temperature and pressure. Copy the following
table which gives the volumes of gases collected and the number of
molecules (X) in 20 litres of nitrogen. You are to complete the table giving
the number of molecules in the other gases in terms of X.
Gas Volume (litres) Number of Molecule
Chlorine 10
Nitrogen 20 X
Ammonia 20
Sulphur dioxide 5

iv. Gas Volume (litres) Number of Molecules
Chlorine 10
Nitrogen 20 X
Ammonia 20
Sulphur dioxide 5
(d) [5]
Copy and complete the table. The table summarizes the observations following the
addition of barium chloride solution and lead nitrate solution to solutions of zinc
salts. If nothing happens write 'no reaction' as shown or write 'white precipitate'.

Barium Chloride solution Lead Nitrate solution
Zinc chloride solution
Zinc nitrate solution No reaction No reaction
Zinc sulphate solution

(e) [5]
i. Calculate the percentage of phosphorus in the fertilizer super-phosphate Ca
(H2PO4). (correct to one decimal place)
(H = 1; O = 16; P = 31; Ca = 40).
ii. Write down and balance the following equation correctly:
Ca3(PO4)2 + H2SO4 → Ca (H2PO4)2 + CaSO4
iii. Copy and complete the following sentence-
Superphosphate is an example of a compound called ................. (acid
salt/basic salt/normal salt).
(f') Write the balanced equations for the following reactions: [5]
i. Dilute hydrochloric acid and sodium sulphite.
ii. Chlorine and hot concentrated potassium hydroxide solution.
iii. An acid and an alkali.
(You must first write "The acid is ......................... and the alkali is
....................... ", then write the equation.)
(g) Copy and complete the following sentences choosing the correct word or
words from those given in brackets at the end of each sentence- [5]

i. ) The properties of the elements are a periodic function of their
........................ (atomic number, mass number, relative atomic mass)
ii. Moving across a ............... of the Periodic Table the elements show
increasing ...................... character (group, period, metallic, non-metallic)
iii. The element at the bottom of a group would be expected to show
..................... metallic character than the element at the top (less, more)
iv. The similarities in the properties of a group of elements is because they
have the same ..................... (electronic configurations, number of outer
electrons, atomic numbers.
(h) Mention the terms defined by the following sentences: [5]
i. The mass of a given volume of gas compared to the mass of an equal
volume of hydrogen.
ii. A soluble base.
iii. The insoluble solid formed when two solutions are mixed together.
iv. Compounds containing carbon and hydrogen only.
v. An acidic solution in which there is only partial ionization of the solute
molecules.

SECTION II (40 marks)
Answer any four questions from this section

Question 2
(a) Write the equation for: [4]
i. The preparation of Hydrogen chloride from Sodium chloride and Sulphuric
acid. State whether the Sulphuric acid should be concentrated or dilute.
ii. The preparation of Ammonia from Ammonium chloride and Calcium
hydroxide.
iii. The reaction of hydrogen chloride with ammonia.
(b) [4]
i. What are the products formed when Ammonia is oxidized with copper
oxide?
ii. Name one lead compound that can be used to oxidize hydrogen chloride to
chlorine.
(c) What is the difference between the chemical nature of an aqueous solution of
hydrogen chloride and an aqueous solution of ammonia? [2]

Question 3
(a) Choosing only words from the following list, write down the appropriate words
to fill in the blanks (i) to (v): [2]
Addition, carbohydrates, CnH2n-2, CnH2n+2, electrochemical, homologous,
hydrocarbons, saturated, substitution, unsaturated.
The alkanes form an (i) .................................. series with the general formula, (ii)
..................................... The alkanes are (iii) ............................................., (iv)
..................... which generally undergo, (v) ................. reactions.

(b) Ethanol can be converted to ethene which can then be changed to ethane.
Choose the correct word or phrase from the brackets to complete the following
sentences: [4]
i. The conversion of ethanol to ethene is an example of .................
(dehydration, dehydrogenation)
ii. Converting ethanol to ethene requires the use of ........................
(concentrated hydrochloric acid, concentrated nitric acid, concentrated
sulphuric acid).
iii. The conversion of ethene to ethane is an example of ....................
(hydration, hydrogenation.)
iv. The catalyst used in the conversion of ethene to ethane is commonly
.................... (iron, cobalt, nickel).
(c) Write down the equation for the preparation of ethyne from calcium carbide.

Question 4
(a) Choose the correct word from the brackets to complete the sentences: (a) (i)
and (a) (iii) [4]
i. Sulphur can be converted to sulphuric acid using .......................
(concentrated/dilute) nitric acid.
ii. Write the equation for reaction in 4 (a) (i).
iii. Sodium nitrate reacting with .................... (concentrated/dilute) sulphuric
acid produces nitric acid.
iv. Write the equation for reaction 4 (a) (iii).

(b) Write the equations for the following reactions: [4]
i. Dilute nitric acid producing carbon dioxide.
ii. Dilute sulphuric acid producing hydrogen.
iii. Between copper and concentrated nitric acid.
iv. Between lead nitrate solution and dilute sulphuric acid.
(c) [2]
i. Classify the solutions of the following as acids, bases or salts: ammonium
hydroxide, barium chloride, sodium chloride, sodium hydroxide, H2SO4
and HNO3.
ii. Explain how a reagent chosen from those in 4 (c) (i) enables you to
distinguish between the two acids mentioned therein.

Question 5 [6]
(a) A metal M forms a volatile chloride containing 65.5% chlorine. If the density
of the chloride relative to hydrogen is 162.5, find the molecular formula of the
chloride. (M = 56, Cl = 35.5)
(b) The reaction 4N2O + CH4→ CO2 + 2H2O + 4N2 takes place in the gaseous
state. If all volumes are measured at the same temperature and pressure, calculate
the volume of dinitrogen oxide (N2O) required to give 150 cm
3
of steam. (N = 14,
O = 16, C = 12, H = 1)
(c) From the equation:
(NH4)2Cr2O7 → Cr2O3 + 4H2O + N2

Calculate:
(i) The volume of nitrogen at STP, evolved when 63g of ammonium dichromate is
heated.
(ii) The mas of chromium (III) oxide (Cr2O3) formed at the same time (N = 14, H
= 1, Cr = 52, 0 = 16).

Question 6 [5]
(a) Choosing only substances from the list given in the box below, write equations
for the reactions which you would use in the laboratory to obtaini.
Sodium sulphate.
ii. Copper sulphate.
iii. Iron (II) sulphate
iv. Zinc carbonate.
Dilute sulphuric acid Copper
Iron
Sodium
Zinc
Copper carbonate
Sodium carbonate

(b) From the formulae listed below, choose one, in each case, corresponding to the
salt having the given descriptions AgCl, CuCO3, CuSO4.5H2O, KNO3, NaCl,
NaHSO4, Pb(NO3)2, ZnCO3, ZnSO4.7H2O [5]
i. An acid salt.
ii. An insoluble chloride.
iii. On treating with concentrated sulphuric acid, this salt changes from blue to
white.
iv. On heating, this salt changes from green to black
v. This salt gives nitrogen dioxide on heating.

Question 7
(a) Zinc is extracted from zinc blende. The zinc blende is roasted. The solid
product is mixed with coke in a blast furnace from which zinc vapour emerges: [5]
i. What is the zinc compound in zinc blende?
ii. Write the equation for the roasting of zinc blende.
iii. What is the purpose of using coke?
iv. What is the reducing agent in this extraction?
v. How is the zinc vapour condensed to liquid?
(b) From the metals copper, iron, magnesium, sodium and zinc, select a different
metal in each case which: [4]
i. Does not react with dilute hydrochloric acid.
ii. Can form 2
+a
nd 3
+
ions
iii. Has a hydroxide that reacts with both acids and alkalis.
iv. Does not react with cold water but reacts with steam when heated.


General Instructions
1. Section I is compulsory. Attempt any four questions from Section II.
2. The intended marks for questions or parts of questions are given in brackets.
SECTION I (40 Marks)
Attempt all questions from this Section
Question 1
(a) Select from the list below the gas that matches the description given in each case and
answer the questions that follow:
Ammonia, chlorine, hydrogen chloride, sulphur dioxide.
(i) Gas A is a reducing agent which contains oxygen.
i. What is the name of gas A?
ii. What will you observe if gas A is bubbled through acidified potassium
dichromate solution?
(ii) Gas B turns moist red litmus paper blue.
i. What is the name of gas B?
ii. Write the equation for the reaction that takes place when gas B is passed over
heated copper oxide.
(iii) When gas C is mixed with gas B, dense white fumes are seen and there is no other
product.
i. What is the name of gas C?
ii. What is the name of the product of the reaction between gas B and gas C? [6]
(b) Samples of the gases O2, N2, CO2 and CO under the same conditions of temperature
and pressure contain the same number of molecules represented by X. The molecules of
oxygen (O2) occupy V litres and have a mass of 8 gms. Under the same conditions of
temperature and pressure:
i. What is the volume occupied by:
(1) X molecules of N2 (2) 3X molecules of CO?
ii. What is the mass of CO2 in grams?
iii. In answering the above questions, which law have you used? (C = 12, N = 14, O
= 16) [6]
(c) The following table shows the tests a student performed on four aqueous solutions A,
B, C and D. Write down on your answer script the observations (i) to (iv) that were made.

Test Observations Conclusions
(i) To solution A, barium chloride
solution and dilute
hydrochloric acid were added.
(i) A contains SO4
2-
ions
(ii) To solution B sodium
hydroxide solution was
added.
(ii) B contains Fe3+
ions
(iii) To solution C ammonium
hydroxide was added
slowly till in excess.
(iii) C contains Cu2+
ions
(iv) To solution D silver nitrate
solution and dilute
nitric acid were added.
(iv) D contains Cl-ions
(d) List 1 contains metal/alloys 1, 2, 3, 4, 5 and list 2 contains their uses A, B, C, D, E.
List 1 List 2
Metal/Alloy
1. Aluminium
2. Lead
3. Brass
4. Iron
5. Zinc
Uses
A. Steel making
B. Aeroplane wings
C. Galvanizing
D. Radiation shield
E. Electrical fittings
Copy and complete the following table writing down the letter for the correct use of each
metal. An answer may be used only once. The first one has been done for you.
Metal 1 2 3 4 5
Uses B
(e) (i) What is meant by a Group in the Periodic Table?
(ii) Within a Group where would you expect to find the element with:
i. The greatest metallic character?
ii. The largest atomic size?
(iii) State whether the ionization potential increases or decreases on going down a Group.
(iv) How many elements are there in Period 2? [5]
(f) (i) What is the type of reaction taking place between ethane and chlorine to form
mono-chloroethane?
(ii) The reaction between ethene and chlorine forms only one product. Name the type of
this reaction.
(iii) (1) Draw the structural formula of ethene.
(2) What is the feature of the ethene structure which allows ethene to react with chlorine
in the way it does? [4]
(g) (i) Calculate the percentage of platinum in ammonium chloroplatinate (NH4)2PtCl6
(Give your answer correct to the nearest whole number).
(ii) The percentage composition of sodium phosphate as determined by analysis is 42.1%
sodium, 18.9% Phosphorus and 39% oxygen. Find the empirical formula of the
compound (work to upto two decimal places).
(H = 1, N = 14, O = 16, Na = 23, P = 31, Cl = 35.5, Pt = 195) [6]
(h) Write the balanced equations for the preparation of the following compounds (as the
major product) starting from iron and using only one other substance:
(i) Iron (II) chloride. (ii) Iron (III) chloride.
(iii) Iron (II) sulphate (iv) Iron (II) sulphide [4]

SECTION II (40 marks)
Answer any four questions from this section

Question 2
(a) (i) Write down the words or phrases from the brackets that will correctly fill in the
blanks in the following sentences:
i. Pure water consists almost entirely of ....................... (ions/molecules)
ii. We can expect that pure water ...................... (will/will not) normally conduct
electricity.
(ii) To carry out the so-called "electrolysis of water", sulphuric acid is added to water.
How does the addition of sulphuric acid produce a conducting solution?
(iii) Copy and complete the following sentence:
With platinum electrodes hydrogen is liberated at the .................. and oxygen at the
.................... during the electrolysis of acidified water?
(iv) When the electrolysis of acidified water is carried out:
i. What is the ratio of the volume of hydrogen produced to the volume of oxygen?
ii. Give the equation for the discharge of ions at the cathode. [7]
(b) Copy and complete the following table: Sodium Phosphorus Formula of chloride [3]
Sodium Phosphorus
Formula of chloride
Physical state of chloride at
room temperature (i.e., solid,
liquid
or gas)
Nature of bonding in chloride.
(i.e., ionic or covalent)

Question 3
In order to obtain 1 tonne of aluminium, the following inputs are required: 4 tonnes of
bauxite, 150 kg. of sodium hydroxide and 600 kg. of graphite. The aluminium compound
in bauxite is aluminium oxide and the main impurity is iron (III) oxide. Aluminium is
obtained by the electrolysis of aluminium oxide dissolved in cryolite.
(a) When bauxite is treated with sodium hydroxide solution what happens to:
i. The aluminium oxide?
ii. The Iron (III) oxide? [2]
(b) (i) Name the process used for the purification of bauxite.
(ii) Write the equation for the action of heat on aluminium hydroxide. [2]
(c) (i) Write the formula of cryolite.
(ii) Write down the word which correctly completes the following sentence:
"By dissolving aluminium oxide in cryolite a ................. (conducting/non-conducting)
solution is produced.
(iii) Why is so much graphite required for this electrolytic process?
(iv) Write the equation for the reaction which takes place at the cathode. [4]
(d) In construction work, why is the alloy of aluminium, i.e., duralumin is used rather
than pure aluminium? [2]

Question 4
(a) (i) What happens when dilute hydrochloric acid is added to lead nitrate I solution?
(ii) Describe the two colour changes which take place when moist blue litmus is placed in
a gas jar of chlorine.
(iii) What is the colour change that takes place when chlorine water is exposed to
sunlight? [4]
(b) Manganese (IV) oxide, Lead (IV) oxide and Red Lead (Pb3O4) react with
concentrated hydrochloric acid, liberating chlorine.
(i) What is the common property being shown by these metal oxides?
(ii) Write the equation for the reaction of concentrated hydrochloric acid with Pb3O4
(iii) What kind of compound can be added to bleaching powder to obtain chlorine? [3]
(c) (i) When moist chlorine reacts with hydrogen sulphide two products are formed:
i. A gas which fumes in moist air; and
ii. A yellow solid.
Name these products.
(ii) What type of reaction is taking place when chlorine acts as a bleaching agent? [3]

Question 5
(a) Write the equation for the action of heat on: (i) ammonium chloride and (ii)
ammonium nitrate? State whether each reaction is an example of thermal decomposition
or thermal dissociation. [4]
(b) (i) What compounds are required for the laboratory preparation of nitric acid?
(ii) Why does pure nitric acid take on a yellowish brown colour when exposed to light?
[3]
(c) Write equations for the following reactions:
i. Copper and concentrated nitric acid.
ii. Copper oxide and dilute nitric acid. [2]
(d) The frst step in the manufacture of nitric acid is the catalytic oxidation of ammonia.
What is the name of the catalyst? [1]

Question 6
(a) Copy and complete the following table. Column 3 has the names of gases to be
prepared using the substance you enter in column 1 along with dilute or concentrated
sulphuric acid as indicated by you in column 2. [8]
Column 1 Column 2 Column 3
Substance reacted with acid Dilute or concentrated sulphuric
acid
Gas
Hydrogen
Carbon dioxide
Only chlorine
(b) Write the equations for the laboratory preparation of:
i. Sodium sulphate using dilute sulphuric acid.
ii. Lead sulphate using dilute sulphuric acid. [2]

Question 7
(a) The list of some organic compounds is given below:
Ethanol, ethane, methanol, methane, ethyne, and ethene.
From the list above, name a compound:
i. Formed by the dehydration of ethanol by concentrated sulphuric acid.
ii. Which will give red precipitate with ammoniacal cuprous chloride solution.
iii. Which forms methanoic acid on oxidation in the presence of copper at 200oC
iv. Which has vapour density 14 and turns alkaline potassium permanganate green.
v. Which forms chloroform on halogenation in the presence of sunlight.
vi. Which decolourises bromine solution in carbon tetrachloride. [6]
(b) Write balanced equations for the preparation of the following:
i. Ethane from sodium propionate.
ii. Ethene from ethanol.
iii. Ethyne from calcium carbide.
iv. thanoic acid from ethane. [4]