MODEL PAPER - 7 [2026] — Science STD 10 — Question

In the following questions, a statement of Assertion is given by the corresponding statement of Reason. Of the statements, mark the correct answer as.

1. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
2. If both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.
3. If Assertion is true, but Reason is false.
4. If Assertion is false, but Reason is true.
5. Both Assertion and Reason are false.

Assertion: Hydrogen is not a metal but it has been assigned a place in the reactivity series of metals.
Reason: Hydrogen has a tendency to lose electron and forms a positive ion H⁺.

In the following questions, a statement of Assertion is given by the corresponding statement of Reason. Of the statements, mark the correct answer as.

1. If both Assertion and Reason are true and Reason is the correct explanation of Assertion.
2. If both Assertion and Reason are true, but Reason is not the correct explanation of Assertion.
3. If Assertion is true, but Reason is false.
4. If Assertion is false, but Reason is true.
5. Both Assertion and Reason are false.

Assertion: The pH of sodium chloride solution is seven.
Reason: Salt of strong acid and a strong base are acidic in nature.

For two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:

1. Both A and R are true, and R is correct explanation of the assertion.
2. Both A and R are true, but R is not the correct explanation of the assertion.
3. A is true, but R is false.
4. A is false, but R is true.

Assertion: Copper displaces silver from silver nitrate solution.
Reason: Copper is more reactive than silver.

For two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:

1. Both A and R are true, and R is correct explanation of the assertion.
2. Both A and R are true, but R is not the correct explanation of the assertion.
3. A is true, but R is false.
4. A is false, but R is true.

Assertion: ln a balanced chemical equation, total mass of the reactants is equal to the total mass of the products.
Reason: Mass can neither be created nor destroyed during a chemical change.

For two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:

1. Both A and R are true, and R is correct explanation of the assertion.
2. Both A and R are true, but R is not the correct explanation of the assertion.
3. A is true, but R is false.
4. A is false, but R is true.

Assertion: Following reaction describes the rusting of iron and is a redox reaction.
4Fe + 3O₂ → 4Fe³⁺ + 60^2-.
Reason: The metallic iron is oxidised to Fe³⁺.

For two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:

1. Both A and R are true, and R is correct explanation of the assertion.
2. Both A and R are true, but R is not the correct explanation of the assertion.
3. A is true, but R is false.
4. A is false, but R is true.

Assertion: MnO₂ + 4HCl → MnCl₂ + Cl₂ + 2H₂O, is a redox reaction.
Reason: MnO₂ oxidises HCl to Cl₂ and gets reduced to MnCl₂.

Assertion (A): When common salt is kept open, it absorbs moisture from the air.
Reason (R): Common salt contains magnesium chloride.

Two statements are given - one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:

1. Both A and Rare true and R is the correct explanation of the Assertion.
2. Both A and R are true but R is not the correct explanation of the Assertion.
3. A is true but R is false.
4. A is false but R is true.

Assertion(A): In a homologous series of alcohols, the formula for the second member is C₂H₅OH and the third member is C₃H₇OH.

Reason(R): The difference between the molecular masses of the two consecutive members of a homologous series is 144.

For question two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:

1. Both A and R are true, and R is correct explanation of the assertion.
2. Both A and R are true, but R is not the correct explanation of the assertion.
3. A is true, but R is false.
4. A is false, but R is true.

Assertion: The process of dissolving an acid or a base in water is highly exothermic reaction.
Reason: Water must always be added slowly to acid with constant stirring.

For two statements are given-one labelled Assertion (A) and the other labelled Reason (R). Select the correct answer to these questions from the codes (a), (b), (c) and (d) as given below:

1. Both A and R are true, and R is correct explanation of the assertion.
2. Both A and R are true, but R is not the correct explanation of the assertion.
3. A is true, but R is false.
4. A is false, but R is true.

Assertion: 2H₂S(g) + O_2(g) → 2S_(g) + 2H₂O_(l) lt is a redox reaction.
Reason: ln redox reaction, oxidation and reduction take place simultaneously.