Class 9 Science 2nd Model Question Paper (CBSE) for Exam Preparation

Class 9 Science Chapter-wise 2nd Model Questions with Answers for Better Exam Practice

2. Model Question Paper

Q9. On converting 25°C , 38°C and 66°C to Kelvin scale , the correct sequence of temperature will be

(A) 298K , 311K and 339K

(B) 298K , 300K and 338K

(C) 273K , 278K and 543K

(D) 298K , 310K and 338K

Ans : (A) 298K , 311K and 339K

Q10 . Choose the correct statement of the following :

(A) conversion of solid into vapours without passing through the liquid state is called vapourisation.

(B) conversion of vapours into solid without passing through the liquid state is called sublimation .

(C)  conversion of vapours into solid without passing through the liquid state is called freezing .

(D) Conversion of solid into liquid is called sublimation .

Ans : (B) conversion of vapours into solid without passing through the liquid state is called sublimation .

Q8. The boiling points of diethyl ether , acetone and n-butyl alcohol are 35°C , 56°C and 118°C respectively . Which one of the following correctly represents their boiling points in Kelvin scale ?

(A) 306K , 329K , 391K

(B) 308K , 329K , 392K

(C) 308K , 329K , 391K

(D) 309K , 392K , 308K

Ans : (C) 308K , 329K , 391K

[Hints: 35+273 = 308k ; 56+273 = 329K ; 118+273 = 391]

9. Which condition out of the following will increase the evaporation of water ?

(A) Increase in temperature of water .

(B) Decrease in temperature of water .

(C) Less exposed surface area of water .

(D) Adding common salt to water .

Ans : (A) Increase in temperature of water .

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Posted 4 months ago