3. Model Question Paper

Choose the correct answers :

Q1. Which of the following materials fall in the category of a ‘‘ Pure Substance ’’ ?

(A) Milk

(B) Air

(C) Wood

(D) Mercury

Ans : (D) Mercury

Q2. Which of the following will show ‘‘ Tyndall effect ’’ ?

(i) Salt solution

(ii) Milk

(iii) Copper sulphate solution .

(iv) Starch solution.

(A)  (i) and (ii) 

(B) (ii) and (iii)

(C)  (iii) and (iv)

(D) (ii) and (iv)

Ans : (D) (i) and (iv)

Q3. Which of the following are compounds ?

(A) Silicon

(B) Carbon-dioxide

(C) Soil

(D) Air

Ans : (B) Carbon-dioxide