CBSE Class 10 Science Sample Paper 2018 Set 04

SECTION : A

1.Identify in the following reaction :

2PbO +C→2Pb +CO₂

d) the substance oxidised and

e) the substance reduced.

2. Name the rule which gives the direction of force experienced by a current carrying conductor when placed in a magnetic field.

3. Thermal power plants are set up near coal or oil fields. Give reason

4. Why is the rate of breathing in aquatic organisms much faster than in terrestrial organisms?

5.When zinc metal is treated with a dilute solution of a strong acid, a gas is evolved, which is utilised in the hydrogenation of oil. Name the gas evolved. Write the chemical equation of the reaction and also write a test to detect the gas formed. 

6. A compound which is prepared from gypsum has the property of hardening when mixed with proper quantity of water. Name the compound. How is it prepared? For what purpose is it used in hospitals ?

7. Illustrate the different pathways in the breakdown of a glucose molecule.

8. Answer the following:-

i)Which gland secretes digestive enzymes as well as hormones ?

ii) Which endocrine gland is present in females , but absent in males ?

iii) Name the hormone essential for carbohydrate, protein and fat metabolism

9. a) Oil and fat containing food items are flushed with nitrogen while packing them. Why?

b) Why do we apply paint on iron articles?

10.a) State two properties of gold which are extreme use to jewellers.

b) Name one metal and non-metal which exists in liquid state at room temperature.

c)Why do we use copper and aluminium wire for the transmission of electric current

11.Explain with electronic dot structure the formation of MgCl₂ by ionic bonding.

12.Write the balanced chemical for the following and identify the type ofreaction in each case.

a) Zinc carbonate(s) Zinc oxide+ Carbondioxide

b) Potassium bromide(aq) + Barium iodide(aq)Potassium iodide+Barium bromide

13. What is solar cell panel ? List two advantages and disadvantages each of using solar cells for producing electricity .

14.What are the environmental consequences of the increasing demand for energy? What steps you suggest to reduce energy consumption?

15.a) What do you mean by magnetic effect of electric current?

b) State Right hand thumb rule.

16. What is solenoid? Draw magnetic field lines for a current carrying Solenoid.

17. One day Suresh connected many household power appliances having a current rating more than 6A to a multi-plug of 6A rating.When he wasabout to switch them on, his elder sister shouted and asked him to remove the appliances from a single socket.

a) According to you, why she would not advice to connect multi-high power appliances on a single socket?

b) What would have happened, if he switched them on?

c) What was the value shown by his sister?

18. Two lamps, one rated 100W at 220V and other 60W at 220V are connected in parallel to the electric supply at 220V.

a) Draw a circuit diagram to show the connections.

b) Calculate the total current drawn from the electric supply. 

19.i) What is refining of a metal ?

ii) Describe the electrolytic refining of copper metal with the help of a labelled diagram.

iii) Mention constituent metals present in bronze.

20.a) You have four solutions A,B,C and D.The pH solution A is 6, B is 9 ,C is 12 and D is 7.

i) Identify the most acidic and most basic solutions.

ii) Arrange the above four solutions in the increasing order of H+ ion concentration

iii) State the change in colour of pH paper on dipping in solution Cand then D.

c) Dry ammonia gas has no action on litmus paper, but a solution of ammonia in water turns red litmus paper blue. Why is it so ?

21.a) Define electric power.

b) How many joules are there in one kilowatt-hour?

c) An electric heater draws current of 10A from a 220V supply.What is the cost of using heater for 5h everyday for 30 days, if the cost of one unit of electric energy is Rs 5.25?

22.a) Draw a neat labelled diagram of human digestive system.

b) Differentiate between arteries and veins

23.a) Define reflex action.

b)Draw a schematic diagram to depict reflex arc

c) Differentiate between sensory and motor nerves.

24. a) What is the conversion of energy in electric generator?

b)State the principle of working of generator.

c) Why is it necessary to earth metallic appliances?

SECTION : B (PBQ)

25.A student tested pH of the distilled water and found the colour changed to

a) Green b) Red

c) Blue d)Yellow

26.A small amount of quick lime is taken in a beaker. Water is added slowly to the beaker.

a) Hissing sound and the solution becomes hot

b) A hissing sound and the solution becomes cold

c) Hissing sound and the solution becomes cold

d) No sound and solution becomes hot

27.Reddish brown deposit observed on irons, when these are kept in Aqueous solution of copper sulphate is that of

a)Copper oxide

b)Copper

c)Copper sulphide

d) Iron sulphate

Please click the link below to download CBSE Class 10 Science Sample Paper 2018 Set D