CBSE Class 10 Science Sample Paper Set N

SECTION-A 

1. State the main difference between an endothermic reaction and an exothermic reaction.

2. Which gas is liberated when a metal reacts with an acid ? How will you test the presence of this gas ?

3. Write the sequence of events taking place in a bio gas plant.

4. A given length of a wire is doubled on itself and this process is repeated once again. By what factor does the resistance of the wire changes ?

5. When a metal X is treated with cold water, it gives a basic salt Y with molecular formula XOH (Molecular mass = 40) and liberates a gas Z which easily catches fire. Identify X, Y, Z. 

6. Classify the following salts into acidic, basic and neutral : Potassium sulphate, ammonium chloride, sodium carbonate, sodium chloride.

7. A zinc plate was put into a solution of copper sulphate kept in a glass container. It was found that blue colour of the solution gets fader and fader with the passage of time. After few days when zinc plate was taken out of the solution, a number of holes were observed on it.

8. A white salt on heating decomposes to give brown fumes and a residue is left behind.

(i) Name the salt.

(ii) Write the equation for the decomposition reaction. 

9. How are the alveoli designed to maximize the exchange of gases ?

10. What is a solar cell panel ? Mention any three of its applications.

11. A current of 5.0 A flows through a 12Ωresistor. What is the rate at which heat energy is produced in the resistor ?

Please refer to attached file for CBSE Class 10 Science Sample Paper Set N