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Water: The Elixir of Life - Water Conservation: Drop by Drop

Grade 3CBSE

Review the key concepts, formulae, and examples before starting your quiz.

🔑Concepts

Water is the most precious natural resource, often called the 'Elixir of Life', and its chemical formula is H2OH_2O.

Nearly 34\frac{3}{4} of the Earth's surface is covered with water, but only a very small percentage is fresh water available for drinking.

Water exists in three states: Solid (ice), Liquid (water), and Gas (water vapor). These states change through heating or cooling.

The Water Cycle is a continuous process involving Evaporation, Condensation, and Precipitation that circulates H2OH_2O between the Earth and the atmosphere.

Water Conservation means using water wisely and avoiding wastage. Methods include turning off taps while brushing and using a bucket instead of a hose to wash cars.

Rainwater Harvesting is a technique used to collect and store rain H2OH_2O for future use instead of letting it run off.

Water pollution is caused by throwing waste into rivers and lakes, making the H2OH_2O harmful for plants, animals, and humans.

📐Formulae

H2OH_2O

Ice (Solid)HeatWater (Liquid)HeatSteam (Gas)\text{Ice (Solid)} \xrightarrow{\text{Heat}} \text{Water (Liquid)} \xrightarrow{\text{Heat}} \text{Steam (Gas)}

Total Water on Earth97% (Saltwater)+3% (Freshwater)\text{Total Water on Earth} \approx 97\% \text{ (Saltwater)} + 3\% \text{ (Freshwater)}

💡Examples

Problem 1:

If a leaking tap wastes 22 liters of H2OH_2O every hour, how much water is wasted in one full day (2424 hours)?

Solution:

2 liters×24=48 liters2 \text{ liters} \times 24 = 48 \text{ liters}

Explanation:

To find the total waste, we multiply the amount of H2OH_2O wasted per hour by the total number of hours in a day.

Problem 2:

What happens to liquid H2OH_2O when it is kept in a freezer at 0C0^\circ C?

Solution:

It turns into Ice (Solid).

Explanation:

When water loses heat, it undergoes a process called freezing, changing its state from liquid to solid.

Problem 3:

Briefly explain the process of Rainwater Harvesting.

Solution:

Collecting rain H2OH_2O from rooftops and storing it in tanks.

Explanation:

Rainwater harvesting helps in increasing the groundwater level and ensures we have H2OH_2O available during dry seasons.