question_answer

   (i) What temperature in Kelvin scale is equal to 50°C? (ii) Describe an activity to show that rate of evaporation increases with surface area. (iii) State two differences between evaporation and boiling.

Answer:

                  (i) 50 + 273 = 323 K                                       (1) (ii) Activity (a) Take little amount of water in three containers which have different surface areas. (b) Keep them in sunlight for 2 hours. (c) Measure the volume of left water in all three containers. Observation The amount of water left will be least in the container having largest surface area among them. Conclusion Greater the surface area, more will be the rate of evaporation.                  (2) (iii) For differences Refer to theory page no.