Question

D. Write true or false. Correct the false statements.
1. Rainwater contains large amounts of dissolved salts.
2. Underground water can be used by digging wells and tube wells.
3. Copper sulphate is soluble in water.
4. Heating causes a solute to dissolve faster in its solution.
5. About 50 per cent of our body is made up of water.
6. Water is used to generate electricity.
7. Acid rain pollutes water bodies and harms aquatic life.
E. Define the following terms.
1. Underground water
4. Water pollution
2. Saturated solution
3. Solubility
5. Water conservation​

Answer 1

Answer:

Explanation:

true or false

1 false  - Rainwater doesn't contains dissolved salts.

2 true -

3 true  

4 true

5 false  - About 70 per cent of our body is made up of water.

6 true  

7 true

define the following

1. Groundwater is the water present beneath Earth's surface in soil pore spaces and in the fractures of rock formations. A unit of rock or an unconsolidated deposit is called an aquifer when it can yield a usable quantity of water

2.Water pollution is the contamination of water bodies, usually as a result of human activities. Water bodies include for example lakes, rivers, oceans, aquifers and groundwater. Water pollution results when contaminants are introduced into the natural environment

3.A saturated solution is a solution that contains the maximum amount of solute that is capable of being dissolved. At 20°C, the maximum amount of NaCl that will dissolve in 100. g of water is 36.0 g. If any more NaCl is added past that point, it will not dissolve because the solution is saturated.

4.The maximum amount of solute that can dissolve in a known quantity of solvent at a certain temperature is its solubility.

5.Water conservation includes all the policies, strategies and activities to sustainably manage the natural resource of fresh water, to protect the hydrosphere, and to meet the current and future human demand. Population, household size and growth and affluence all affect how much water is used.

Answer 2

Question D: The correct answers are as follows:

1. False- Rainwater contains very few dissolved salts and minerals and has high amounts of dissolved gases.

2. True. (Digging wells and tube wells give us access to the water level below the ground.)

3. True. (Water is a polar solvent that easily dissolves inorganic salts like copper sulfate.)

4. True. (Heating disperses the solute quickly because of which it dissolves faster.)

5. False- About 60 percent of our body is water.

6. True. (Water power is utilized in turbines to produce electricity, which is also called hydroelectricity.)

7. True (Acid rain contains acids like sulphuric acid and nitric acid that harm the water bodies by changing their composition and certain metals by dissolving them.)

Question E: The definitions are as follows:

1. Underground water- The water stored below the surface of the land is called underground water. They are mainly stored above the rock bed and in cracks and aquifers.

2. Saturated solution- A solution that cannot dissolve any more solute is a saturated solution. Such a solution has its maximum concentration of solute.

3. Solubility- Solubility is the ability of a solute to dissolve in a solvent and form a solution.

4. Water pollution- Water pollution refers to the contamination of the water bodies by the release of harmful chemicals in it such as untreated sewage, chemicals from industries, smokes from vehicles, etc.

5. Water conservation- Water conservation is the process of saving water by reducing its unnecessary wastage. Water conservation is essential nowadays as there is an increase in population and a high demand for clean drinking water.