Which of the following are homogeneous in nature?
(i) Ice
(ii) Wood
(iii) Soil
(iv) Air
(a) (i) and (iii)
(b) (ii) and (iv)
(c) (i) and (iv)
(d) (iii) and (iv)
Answer: C
Solution: A mixture is called homogeneous, if the percentage of constituent substances will be same in any part of that mixture. The density of any sample will also be same in homogeneous mixture. If a sample is not homogeneous, it is called heterogeneous. All the pure substances will be homogeneous. Ice is a pure substance; hence it is homogeneous. Air is a homogeneous mixture of multiple gases. Soil and wood or not homogeneous. Hence, the correct option of this question is C.