Have you ever wondered what makes up most of our bodies and Earth's surface? The answer is water! Water is a clear liquid that we drink every day. It covers most of the Earth and is important for all living things to stay healthy and alive. Our bodies need water to work properly, like helping us digest food and stay cool. Plants, animals, and humans all need water to survive. Without water, life on Earth wouldn’t be possible. It's also used for washing, cooking, and cleaning.
Think about it—every living creature, from the tiniest insect to the largest animal, needs water to stay alive and healthy. Isn't that amazing?
Yes, ice and water are two different forms, or states, of the same substance. This means that even though they look and behave differently, they are made of the same basic material.
For example:
So, while ice and water behave differently, they are actually the same substance in different states.
Do you know, Where the water goes after the rain stops?
Can you explain where the water goes when we sprinkle it on a hot pan while making dosa and it disappears?
The water sprinkled on the hot pan gets converted into steam, which is actually water vapor. Some of this vapor condenses back into water droplets.
Water Vapour in Steam
Water vapour is not visible on its own. However, when it condenses into tiny droplets of water, as seen in steam, it becomes visible.
Is it because of:
(i) water seeping into the ground,
(ii) evaporation of water, or
(iii) both.
The answer is (iii) both
Can you explain why water droplets form on a cold water bottle when it's taken out of the fridge?
Water droplets form on the cold water bottle because water vapor in the air touches the cold surface and changes into liquid water. This process is called condensation.
- Humidity: Humidity refers to the amount of water vapor present in the air.
Water can be seen in three different states in our daily life: solid, liquid, and gas.
Can we change the state of water by adding or removing heat? If yes, how?
Yes, we can change the state of water by adding or removing heat. When we heat water, it turns into steam (gas). When we cool water, it turns into ice (solid). By changing the temperature, we can make water switch between liquid, gas, and solid states.
Let’s discuss melting and freezing:
What is an Atmospheric Water Generator (AWG) Machine?
- An Atmospheric Water Generator (AWG) machine is a device that produces drinkable water by collecting moisture from humid air.
- How Does it Work?: The AWG machine works by cooling the air, which causes the water vapor in the air to condense into liquid water. This process is similar to the way droplets of water form on the outside of a cold glass of ice water.
Can you explain why clothes dry faster on a windy day?
Clothes dry faster on a windy day because there is more air in contact with the cloths. This air takes away moisture with it and helps increase the rate of evaporation,
Factors affecting evaporation:
Humidity on Rainy Days
- Humidity refers to the amount of water vapor present in the air.
- On rainy days, the air contains more water vapor, which increases humidity.
- That's why cloths and sweat take more time to dry on rainy days.
![]() |
Download the notes
Chapter Notes: A Journey through States of Water
|
Download as PDF |
Can you explain why we feel cooler under a fan?
We feel cooler under a fan because the moving air helps evaporate sweat from our skin which takes away heat with it, which cools us down.
Cooling effect of evaporation
When water evaporates, it absorbs heat from its surroundings, causing a cooling effect. This phenomenon can be observed in various daily activities and objects.
Examples:
Why Does Water Vapour in the Air Rise?
When air contains a lot of water vapour, it becomes lighter than the surrounding air. This is similar to how gas balloons filled with lighter gases rise in the atmosphere. The water vapour in the air makes it less dense, allowing it to rise higher in the atmosphere.
100 videos|261 docs|49 tests
|
1. What are the different states of water? | ![]() |
2. How can we change the states of water? | ![]() |
3. What factors influence the speed of evaporation? | ![]() |
4. How do clouds form and lead to rain? | ![]() |
5. What is the cooling effect of evaporation? | ![]() |