CBSE Class 10 Science Practical Skills Sample Paper Set 03

SECTION A

1. To prepare a colloidal solution of starch we should

(a) add starch powder to boiling water and cool.

(b) add starh powder to cold water and boil.

(c) heat starch powder, add it to cold water and then bring to boil.

(d) add a thin paste of starch to boiling water while stirring.

2. To prepare iron sulpide, by heating a mixture of iron filings and sulphur powder, we should use a

(a) copper dish.

(b) watch glass.

(c) china dish.

(d) petri dish.

3. When a mixture of common salt and ammonium chloride is heated, it is observed that

(a) Solid common salt gets diposited on the cooler parts of the funnel while solid ammonium chloride remains in the china dish.

(b) Mixture of common salt and ammonium chloride turns into greenish crystals when allowed to cool.

(c) Ammonium chloride gets deposited on the cooler parts of the funnel and solid common salt remains in the china dish.

(d) droplets containing both common salt and ammonium chloride appear on the upper part of the funnel while some molten mixture of common salt and ammonium chloride remains in the china dish. 

4. To check the cooling caused by evaporation of alcohol

(a) The thermometer is first dipped in alcohol and then left in air and decrease in temprature in noted with time.

(b) A plug of cotton is dipped in alcohol and attached to the bulb of the thermometer. This is then kept under a fan and a decrease in temperature in noted with time.

(c) A plug of cotton is dipped in hot alcohol and attached to the bulb of the thermometer. This is then kept in sun the temperature is noted with time.

(d) A plug of cotton is dipped in alcohol and is attached to the bulb of the thermometer. The decrease in temprature is then noted with time.

5. While determining the density of a copper piece using a spring balance and a measuring cylinder, Seema carried out the following procedure :

i. noted the water level in the measuring cylinder without the copper piece

ii. immersed the copper piece in the water

iii. noted the water level in the measuring cylinder with the coper piece inside it.

iv. removed the copper piece from the water and immediately weighed it using a pring balance.

The wrong step in the procedure is

(a) step (i)

(b) step (ii)

(c) step (iii)

(d) step (iv)

6. The temprature-time variation graphs, as obtained by four students A, B, C and D are as shown. The graph, likely to be correct is that of student.

(a) A.

(b) B.

(c) C.

(d) D.

Please click the link below to download CBSE Class 10 Science Practical Skills Sample Paper Set C