Observation and Formula for the Product Formed
Upon adding water to solid calcium oxide, an exothermic reaction takes place, resulting in the formation of calcium hydroxide. The observation includes the release of heat, formation of a white precipitate, and the solution turning alkaline due to the formation of calcium hydroxide. The balanced chemical equation for this reaction is:
CaO (s) + H2O (l) → Ca(OH)2 (aq)

Application of Paint on Iron Articles

Prevention of Rusting:
One of the primary reasons for applying paint on iron articles is to prevent rusting. Iron reacts with oxygen and moisture in the air to form iron oxide, commonly known as rust. By applying paint as a protective layer, the iron surface is shielded from direct contact with oxygen and moisture, thus inhibiting the rusting process.

Enhanced Aesthetics:
Painting iron articles not only protects them from corrosion but also enhances their visual appeal. Different colors and finishes can be used to match the surrounding decor or provide a specific aesthetic look, making the iron articles more attractive.

Improved Durability:
Paint acts as a barrier against environmental elements such as UV rays, moisture, and chemicals, thereby extending the lifespan of iron articles. It provides an additional layer of protection that helps maintain the structural integrity of the iron and prevents degradation over time.

Easy Maintenance:
Painted iron articles are easier to clean and maintain compared to bare iron surfaces. The smooth surface of paint makes it easier to remove dirt, dust, and other contaminants, ensuring that the iron articles retain their appearance and functionality for a longer period.
In conclusion, the application of paint on iron articles serves multiple purposes, including preventing rusting, enhancing aesthetics, improving durability, and facilitating easy maintenance. It is an essential step in preserving the quality and longevity of iron products.