Explanation:

• Cloud seeding is a weather modification technique used to stimulate rainfall by introducing certain substances into clouds to encourage the formation of raindrops.
• The most commonly used chemicals are Silver Iodide (AgI) and Potassium Iodide (KI) because their crystalline structure closely resembles that of natural ice. This allows them to act as nuclei around which moisture condenses, forming raindrops.
• This method is also used for reducing air pollution by washing out suspended particulate matter from the atmosphere.
• Other chemicals like dry ice (solid CO₂) or liquid propane may also be used, but silver iodide and potassium iodide remain the most widely preferred due to their high efficiency in ice crystal formation.

Source: Environment (N.C.E.R.T)