Q1: A common disinfectant used in village wells for disinfection of water is

ANS:D - potassium permanganate

Potassium permanganate (KMnO4) is a chemical compound commonly used as a disinfectant in village wells and other water sources. Here's a more detailed explanation of its properties and usage:

1. Oxidizing Agent: Potassium permanganate is a strong oxidizing agent, meaning it can readily transfer oxygen atoms to other substances. This property allows it to react with organic matter and microorganisms, effectively destroying them and making water safer to drink.
2. Disinfection: When potassium permanganate is added to water, it undergoes a reaction that produces manganese dioxide (MnO2) and oxygen (O2). The oxygen released during this reaction helps in disinfecting the water by oxidizing and killing harmful bacteria, viruses, and other pathogens present in it.
3. Removal of Iron and Manganese: Potassium permanganate is also effective in removing iron and manganese from water. These metals often cause unpleasant tastes, odors, and discoloration in water. Potassium permanganate oxidizes these metals, converting them into insoluble forms that can be filtered out, thereby improving the overall quality of the water.
4. Ease of Use: Potassium permanganate is available in solid crystal form, which can be easily dissolved in water to create a disinfecting solution. It can be added directly to the water source, such as a village well, in measured quantities to achieve the desired level of disinfection.
5. Cost-Effectiveness: Compared to other disinfection methods, potassium permanganate is relatively inexpensive. Its affordability makes it a practical choice for disinfecting large volumes of water in community wells and other similar settings.
6. Precautions: While potassium permanganate is an effective disinfectant, it should be handled with care due to its strong oxidizing properties. It can cause skin irritation and staining, and it should not be ingested in large quantities. Proper dosing and handling procedures should be followed to ensure safe and effective disinfection.