Water

There are some key terms that will be helpful to know when studying water and its properties. Understanding these terms will help in identifying the differences between substances that contain water and those that don't, as well as how to test if water is pure.

1. Anhydrous

Definition: Without water.

2. Hydrous

Definition: With water.

3. Water of Crystallisation

Definition: Water that is chemically bonded to the structure of a crystal salt.

Potable Water

It undergoes several processes to remove harmful substances such as bacteria, dirt, and chemicals.

River water can be treated through the following steps:

Stages of Water Treatment

• Filtration: The river water is passed through filter beds to remove large particles, such as dirt, sand, and gravel.
• Sedimentation: The water is left still in tanks, allowing solid particles to settle to the bottom.
• Chlorination: Chlorine is added to the water to kill bacteria and other microorganisms, ensuring the water is safe to drink.

Why is Chlorine Added?

Chlorine is added to kill bacteria and other harmful microorganisms. This ensures the water is free from pathogens and safe for human consumption.

How is Sedimentation Carried Out?

Sedimentation involves leaving the water in large tanks, where solid particles settle at the bottom due to gravity. This step helps in removing large, insoluble particles from the water before further filtration and treatment.

Testing for Pure or Potable Water

• Method: Boil the water and observe the boiling point.
• Result: Pure water will boil sharply at 100°C. Any deviation indicates impurities in the water.