NCERT Book Class 9 Science Solutions and Answers

Chapter 1
1. (c) 2. (c) 3. (c) 4. (d)
5. (c) 6. (a) 7. (b) 8. (c)
9. (a) 10. (c)

11. It’s freezing point will be below 0°C due to the presence of a non-volatile impurity in it.

12. Since ice and water are in equilibrium, the temperature would be zero. When we heat the mixture, energy supplied is utilized in melting the ice and the temperature does not change till all the ice melts because of latent heat of fusion. On further heating, the temperature of the water would increase. Therefore the correct option is (d).

13. (a) cooling
(b) stronger
(c) liquid, gaseous
(d) sublimation, liquid
(e) evaporation

14. (a) — (iii)
(b) — (iv)
(c) — (v)
(d) — (ii)
(e) — (i)

15. (a) — (iv)
(b) — (iii)
(c) — (v)
(d) — (ii)
(e) — (i)

16. Yes, this is true. In both the phenomena, there is movement of particles from region of higher concentration to that of lower concentration. However, in the case of osmosis the movement of solvent is through a semi permeable membrane which is permeable only to water molecules.

Please refer to attached file for NCERT Class 9 Science Solutions and Answers