MCQ Detailed View

Potassium nitrate (KNO₃) is a chemical compound widely used in agriculture and industry. Its most common application is as a fertilizer. It is a source of both potassium (K) and nitrogen (N), which are essential nutrients for plant growth. Nitrogen promotes leafy growth, while potassium improves overall plant health, disease resistance, and fruit quality.

In agriculture, potassium nitrate is often used for high-value crops such as fruits, vegetables, and flowers. It is particularly useful in hydroponic systems and foliar sprays because it dissolves easily in water, allowing plants to absorb nutrients efficiently.

Apart from fertilizers, potassium nitrate also has applications in food preservation, fireworks, and gunpowder production due to its oxidizing properties. Historically, it has been used in medicine, such as in some traditional treatments for heart and urinary problems, but this is not its main use today.

It is important to note that potassium nitrate is not used as salt or glass. Regular table salt is sodium chloride (NaCl), and glass is primarily made from silica (SiO₂) and other additives.

The chemical formula of potassium nitrate is KNO₃, and it appears as a white crystalline solid. It is soluble in water and stable under normal conditions. Its dual nutrient content makes it a highly effective fertilizer compared to single-nutrient options.

In conclusion, the main use of potassium nitrate is in fertilizers (Option 2). Understanding its applications is part of chemistry knowledge because it links chemical composition to real-world industrial and agricultural uses.