NCERT Solutions for Class 6th Science

Chapter 14 - WATER

(Complete Downloadable Chapter Solution PDF file is at the bottom of the page)

 

Q.1      Fill up the blanks in the following:

           (a) The process of changing of water into its vapour is called _________________.

           (b) The process of changing water vapour into water is called _________________.

           (c) No rainfall for a year or more may lead to _________________ in that region.

           (d) Excessive rains may cause _________________.

Ans    (a) The process of changing of water into its vapour is called _evaporation_.

           (b) The process of changing water vapour into water is called _condensation_.

           (c) No rainfall for a year or more may lead to _drought_ in that region.

           (d) Excessive rains may cause _flood_.

Q.2      State for each of the following whether it is due to evaporation or condensation:

           (a) Water drops appear on the outer surface of a glass containing cold water.

           (b) Steam rising from wet clothes while they are ironed.

           (c) Fog appearing on a cold winter morning.

           (d) Blackboard dries up after wiping it.

           (e) Steam rising from a hot girdle when water is sprinkled on it.

Ans     (a) Water drops appear on the outer surface of a glass containing cold water. (CONDENSATION)

           (b) Steam rising from wet clothes while they are ironed. (EVAPORATION)

Q.3      Which of the following statements are “true”?

(a) Water vapour is present in air only during the monsoon. ( )

(b) Water evaporates into air from oceans, rivers and lakes but not from the soil.( )

(c) The process of water changing into its vapour, is called evaporation.( )

(d) The evaporation of water takes place only in sunlight.( )

(e) Water vapour condenses to form tiny droplets of water in the upper layers of air where it is cooler.( )

Q.4      Suppose you want to dry your school uniform quickly. Would spreading it near an anghiti or heater help? If yes, how?

Q.5      Take out a cooled bottle of water from refrigerator and keep it on a table. After some time you notice a puddle of water around it. Why?

Q.6      To clean their spectacles, people often breathe out on glasses to make them wet. Explain why the glasses               become wet.

Ans      When a person breathes out on glasses, carbon dioxide along with some amount of water vapour comes                out in exhaled air. This water vapour condenses on the glasses and thus the glasses become wet.

Q.7      How are clouds formed?

Q.8      When does a drought occur?