Chemistry Specimen Paper 2025-2026 (English Medium) ICSE Class 10 Question Paper Solution

Which of the following will dissociate in aqueous solution to give a positive ion other than hydronium ion and a negative ion other than hydroxyl ion?

KOH

dil. HCl

NaCl

CH₃COOH

A compound P is heated in a test tube with sodium hydroxide solution. A red litmus paper held at the mouth of the test tube turns blue.

Which of the following could compound P be?

Zinc sulphate

Copper sulphate

Ferrous sulphate

Ammonium sulphate

Assertion (A): Aqueous solution of potassium chloride can conduct electricity.

Reason (R): Conduction of electric current is due to the presence of free ions.

(A) is true and (R) is false.

(A) is false and (R) is true.

Both (A) and (R) are true and (R) is the correct explanation of (A).

Both (A) and (R) are true, but (R) is not the correct explanation of (A).

Identify the ion that contains one lone pair of electrons.

OH⁻¹

H₃O⁺

\[\ce{NH^+_4}\]

H⁺

Four reactions are shown below in the diagram:

1.	2.
3.	4.

Which reactions produce water?

1 and 2

1 and 3

3 and 4

2 and 3

When compound X reacts with dilute sulphuric acid, it releases a gas that turns acidified potassium dichromate solution from orange to green. Which of the following could be compound X?

Lead nitrate

Copper carbonate

Sodium chloride

Potassium sulphite

The volume occupied by 2 moles of a gas at STP is ______.

22.4 L

2.24 L

44.8 L

4.48 L

Identify from the following metal oxides which can react with an acid as well as an alkali.

Silver oxide

Calcium oxide

Copper(II) oxide

Aluminium oxide

The structures of four hydrocarbons are shown below:

How many isomers of butene are shown in the above structures?

1

2

3

4

Which element amongst the following has the largest atomic radius?

Al

S

Mg

Na

For which pH change is there the maximum increase in acidity?

The equation below shows the reaction between element ‘X’ and dilute sulphuric acid.

\[\ce{X_{(s)} + H2SO4_{(aq)} -> XSO4_{(aq)} + H2_{(g)}}\]

Which particles are responsible for conducting electricity in dilute sulfuric acid and compound XSO₄?

Electrons

Only positive ions

Only negative ions

Both positive and negative ions

Methanol and ethanol belong to the same homologous series.

What does this statement mean?

Their molecules contain atoms only of carbon and hydrogen.

Their molecules have the same number of carbon atoms.

They have the same functional group.

They have the same relative molecular mass.

The ratio between the volumes occupied by 22 grams of carbon dioxide and 10 grams of hydrogen gas is ______.

2.2 : 1

1 : 2.2

1 : 10

10 : 1

In the process of electrorefining copper, as shown in the diagram below, which of the following statements is correct?

The anode is made of pure copper.

The cathode is made of impure copper.

Copper is deposited at the anode.

Copper ions from the anode move to the cathode and get deposited as pure copper.

Electroplating steel objects with silver involves a three-step process.

Step 1: A coating of copper is applied to the object.

Step 2: A coating of nickel is applied to the object.

Step 3: The coating of silver is applied to the object.

(a) A diagram of the apparatus used for step 1 is shown.

1. The chemical process taking place on the surface of the object is \[\ce{Cu^2+_{ (aq)} + 2e- ->Cu_{(s)}}\].
   What is the observation seen on the surface of the object?
2. Explain why the concentration of copper ions in the electrolyte remains constant throughout step 1. 

(b) Give two changes which would be needed in order to coat nickel onto the object in step 2.

(c) Write down the reaction taking place at the positive electrode during step 3.

Identify the following:

A bond formed between two atoms by sharing of a pair of electrons, with both electrons being provided by the same atom.

Identify the following:

A salt formed by the complete neutralization of an acid by a base.

Identify the following:

A reaction in which the hydrogen of an alkane is replaced by a halogen.

Identify the following:

The energy required to remove an electron from a neutral gaseous atom.

Identify the following:

A homogenous mixture of two or more metals or a metal and a non-metal in a definite proportion in their molten state.

When dilute sulphuric acid reacts with zinc granules, the gas evolved is ______, which can be tested using a burning splint.

hydrogen

carbon dioxide

A solution of copper(II) sulphate in sodium hydroxide solution forms a ______ precipitate.

pale blue

green

In methane, each hydrogen atom share(s) ______ electron(s) with the central carbon atom to complete its valence shell.

one

two

The electron affinity of element X is greater than that of element Y. The oxidising power of X is likely to be ______ than that of element Y.

more

less

The naturally occurring compound of a metal from which the metal can be extracted is called its ______.

ore

mineral

Match the following from Column A with Column B.

Give the IUPAC name of the following organic compound:

\[\begin{array}{cc}
\ce{\phantom{..}H\phantom{..}H\phantom{..}OH}\\
|\phantom{...}|\phantom{...}|\\
\ce{H-C-C-C-H}\\
|\phantom{...}|\phantom{...}|\\
\ce{H\phantom{..}H\phantom{..}H}
\end{array}\]

Give the IUPAC name of the following organic compound:

\[\begin{array}{cc}
\ce{H\phantom{..}H\phantom{..}H\phantom{..}H\phantom{..}H}\\
|\phantom{...}|\phantom{...}|\phantom{...}|\phantom{...}|\\
\ce{H-C=C-C-C-C-H}\\
\phantom{.......}|\phantom{...}|\phantom{...}|\\
\ce{\phantom{.......}H\phantom{..}H\phantom{..}H}
\end{array}\]

Draw the structural formula for the following:

But-2-yne

Draw the structural diagram for the following compound: 

1, 1, 1-trichloromethane

Draw the structural diagram for the following compound.

Pentan-2-ol

Give one significant observation when excess of chlorine gas reacts with ammonia.

State observation:

Zinc nitrate crystals are strongly heated.

Give reasons:

When ammonia gas is passed over black copper oxide in a combustion tube, a reddish-brown substance is left behind.

Give reasons:

Quick lime is not used to dry hydrogen chloride gas.

The electron affinity of an element X is greater than that of element Y.

How is the oxidising power of X likely to compare with that of Y?

The electron affinity of an element X is greater than that of element Y.

How is the electronegativity of X likely to compare with that of Y?

The electron affinity of an element X is greater than that of element Y.

State whether X is likely to be placed to the left or to the right of Y in the periodic table.

State your observation of the following case:

When calcium hydroxide is heated with ammonium chloride crystals.

Write a balanced chemical equation for the following reaction:

Nitric acid reacts with zinc carbonate.

Write a balanced chemical equation for the following reaction:

Concentrated sulphuric acid is added to hydrated copper sulphate.

Name the main constituent metal in the following alloys:

Duralumin

Name the metals present in the following alloys:

Brass

Write the balanced chemical equation for the laboratory preparation of hydrogen chloride gas.

Write a balanced chemical equation for the following: 

Bromine gas is passed over ethene in the presence of carbon tetrachloride.

1. Name the coloured gas that evolved when Abhishek heated the salt strongly.
2. Which cation was present in the sample given to Abhishek?
3. Identify the salt given to Abhishek for analysis.

In a round bottom flask, a mixture of ethanol, acetic acid and concentrated sulphuric acid was heated.

1. Name the type of reaction occurring in the above setup.
2. What is the role of sulphuric acid in this reaction?
3. State one observation that takes place during the reaction.

Identify the reactant and write the balanced equation for the following:

Nitric acid reacts with compound Q to give a salt Ca(NO₃)₂, water and carbon dioxide.

What will be the mass of carbon dioxide that will contain the same number of molecules as present in 3.2 g of oxygen gas? [At. wt: O = 16, C = 12]

State the property exhibited by sulphuric acid in the following reaction:

Sulphur with concentrated sulphuric acid.

State the property exhibited by sulphuric acid in the following reaction:

Conversion of ferrous sulphide to hydrogen sulphide gas using sulphuric acid.

State the property exhibited by sulphuric acid in the following reaction:

Ethanol with concentrated sulphuric acid.

Write the equation of the following laboratory preparations:

Ethyne from calcium carbide.

Give a balanced equation for the following:

Conversion of acetic acid to ethyl acetate.

Give a balanced equation for the following:

Laboratory preparation of nitric acid.

A student was asked to perform an experiment in the laboratory based on the instructions given:

Observe the picture given below and state one observation for the experiment you would notice on mixing the given solution.

A student was asked to perform an experiment in the laboratory based on the instructions given:

Observe the picture given below and state one observation for the experiment you would notice on mixing the given solution.

You are provided with the list of chemicals mentioned below in the box:

Using suitable chemicals from the list given, write a balanced chemical equation for the preparation of the salt mentioned below:

Copper sulphate

You are provided with the list of chemicals mentioned below in the box:

Using suitable chemicals from the list given, write a balanced chemical equation for the preparation of the salt mentioned below:

Sodium zincate

Solid ammonium dichromate decomposes as under:

\[\ce{(NH4)2Cr2O7 ->N2 + Cr2O3 + 4H2O}\]

If 126 g of ammonium dichromate decomposes, calculate:

1. the number of moles of ammonium dichromate that undergoes decomposition.
2. the mass of chromic oxide formed at the same time.
3. the volume of nitrogen gas evolved at STP.

[At. wt: N = 14, Cr  = 52, O = 16, H = 1]

Identify the reactant P in the following reaction: 

\[\ce{Copper oxide + P → Copper + water}\]

Identify the reactant Q in the following reaction: 

\[\ce{Iron pyrite + Q → Iron oxide + Sulphur dioxide}\]

Identify the reactant R in the following reaction: 

\[\ce{Sodium chloride + R → Sodium nitrate + Silver chloride}\]

Give reasons for the following:

Nitric acid does not normally liberate hydrogen gas when it reacts with active metals.

Give reasons for the following:

Silver-plated cutlery is not considered as pure silver.

The following question relate to the extraction of aluminium by electrolysis.

Name the other aluminium containing compound added to alumina.

The following question relate to the extraction of aluminium by electrolysis.

Give the equation for the reaction that takes place at the cathode.

Write balanced chemical equation for action of warm water on AIN.

Give a balanced equation for the following:

Oxidation of carbon with conc. nitric acid.

Give a balanced equation for the following:

Laboratory preparation of ethanol by using chloroethane and aqueous sodium hydroxide.

Rohit has solution X, Y and Z that has pH 2, 7 and 13 respectively.

Which solution will liberate sulphur dioxide gas when heated with sodium sulphite?

Rohit has solution X, Y and Z that has pH 2, 7 and 13 respectively.

Which solution will liberate ammonia gas when reacted with ammonium chloride?

Rohit has solution X, Y and Z that has pH 2, 7 and 13 respectively.

Which solution will not have any effect on litmus paper?

State giving reasons if zinc and aluminium can be distinguished by heating the metal powder with a concentrated sodium hydroxide solution.

State giving reasons if calcium nitrate and lead nitrate can be distinguished by adding ammonium hydroxide solution to the salt solution.

Draw the electron dot structure for the following:

Ammonium ion

[At. no.: N = 7, H = 1]

Write balanced chemical equations for the following conversions (A to C):

L, M and N are three elements with atomic numbers 13, 7 and 10 respectively. Answer the following question using only the alphabets given. Do not identify the elements.

Which element can combine with hydrogen to form a gas which produces dense white fumes with concentrated HCl?

L, M and N are three elements with atomic numbers 13, 7 and 10 respectively. Answer the following question using only the alphabets given. Do not identify the elements.

Which element has zero electron affinity?

L, M and N are three elements with atomic numbers 13, 7 and 10 respectively. Answer the following question using only the alphabets given. Do not identify the elements.

Which element can form an ionic compound with oxygen?