The following 20 Multiple Choice Questions (MCQ) are based on
Chapter 8: A Journey through States of Water from the NCERT Class 6
Science textbook Curiosity. Each question has four options - select the
best answer and click to check.
Instructions: Read each question carefully. Choose the most
appropriate option from (a), (b), (c), or (d). Click
Show Answer to reveal the correct answer with explanation.
Multiple Choice Questions
1Ice and liquid water are:
(a) Different states of the same substance
(b) Different elements
(c) Unrelated materials
(d) A mixture and a metal
(a) is correct
A change of state alters form, not chemical identity.
2Water vapour is water in the:
(a) Solid state
(b) Liquid state only
(c) Metallic state
(d) Gaseous state
(d) is correct
Invisible water vapour mixes with air.
3Liquid water changing into vapour is called:
(a) Freezing
(b) Melting
(c) Evaporation
(d) Condensation
(c) is correct
Surface water particles escape into the air as vapour.
4Water vapour changing into liquid is:
(a) Freezing
(b) Condensation
(c) Evaporation
(d) Melting
(b) is correct
Cooling brings vapour particles together as droplets.
5Ice changing into liquid water is:
(a) Melting
(b) Freezing
(c) Condensation
(d) Evaporation
(a) is correct
Heat changes solid ice to liquid water.
6Liquid water changing into ice is:
(a) Melting
(b) Evaporation
(c) Condensation
(d) Freezing
(d) is correct
Cooling removes heat until the liquid solidifies.
7Wet clothes dry because water:
(a) Changes into ice
(b) Turns into cloth
(c) Evaporates into the air
(d) Disappears from matter
(c) is correct
Liquid water becomes invisible vapour and mixes with the surrounding air.
8Water droplets outside a cold glass come mainly from:
(a) The table producing water
(b) Water vapour in air condensing
(c) Water leaking through intact glass
(d) Ice turning directly into droplets outside
(b) is correct
Air near the cold surface cools and its vapour condenses.
9Which condition speeds evaporation?
(a) Higher temperature
(b) Lower temperature
(c) Still humid air
(d) Smaller exposed surface
(a) is correct
Heating gives more surface particles enough energy to escape.
10Spreading wet clothes speeds drying by increasing:
(a) Water mass
(b) Humidity
(c) Thickness
(d) Surface area
(d) is correct
More water is exposed to moving air at the same time.
11Wind speeds evaporation because it:
(a) Freezes the cloth
(b) Stops particle motion
(c) Carries away water vapour near the surface
(d) Adds liquid water
(c) is correct
Removing moist air maintains a gradient for further evaporation.
12High humidity generally makes evaporation:
(a) Independent of air
(b) Slower
(c) Faster
(d) Impossible in every case
(b) is correct
Moist air has less capacity to accept additional water vapour.
13Evaporation causes cooling because:
(a) Higher-energy particles leave the surface
(b) It adds heat to the liquid
(c) All particles stop
(d) Water becomes heavier
(a) is correct
The remaining liquid has lower average energy.
14An earthen pot cools water because water seeps through tiny pores and:
(a) Freezes inside
(b) Boils continuously
(c) Turns into clay
(d) Evaporates from the outer surface
(d) is correct
Evaporation removes heat from the pot and water.
15Clouds form when rising moist air cools and water vapour:
(a) Disappears
(b) Turns into oxygen
(c) Condenses on tiny particles
(d) Becomes sunlight
(c) is correct
Countless tiny droplets or ice crystals make a cloud.
16Rain begins when cloud droplets:
(a) Stop colliding
(b) Grow heavy enough to fall
(c) All evaporate
(d) Become dust
(b) is correct
Droplets merge or grow until air can no longer support them.
17Which is solid water in nature?
(a) Snow
(b) Rain
(c) Water vapour
(d) Dew
(a) is correct
Snow consists of ice crystals.
18Which sequence is part of the water cycle?
(a) Freezing - magnetism - rusting
(b) Digestion - respiration - growth
(c) Melting - filtration - reflection
(d) Evaporation - condensation - precipitation
(d) is correct
Water circulates between surface and atmosphere through these changes.
19Boiling differs from evaporation because boiling occurs:
(a) Only below freezing
(b) Without bubbles
(c) Throughout the liquid at a particular temperature
(d) Only at the surface at any temperature
(c) is correct
Boiling forms vapour bubbles within the liquid.
20The amount of water on Earth is continually reused mainly through:
(a) Handpicking
(b) The water cycle
(c) Magnetic attraction
(d) Food testing
(b) is correct
State changes and movement recycle water among oceans, land, air and living things.
