Q1. Examine the surface of a piece of sodium just taken out of the bottle. Cut the piece of the sodium in half with a knife and examine the freshly cut surface.
i. Comment on the appearance of the surface before and after cut.
ii. How is sodium stored?
iii. Is the metal reactively harder or soft?
i. Before the sodium is cut, its surface appears dull and silvery. However, upon cutting, the freshly cut surface gives off a shiny appearance due to the exposure to air. The surface may also appear to be slightly tarnished due to the electrochemical reaction with the air's moisture and carbon dioxide.
ii. Sodium is stored in an inert atmosphere and is usually immersed in mineral oil. This is because sodium reacts explosively with water and air, and an inert atmosphere is necessary to prevent such reactions. Immersion in oil also serves as a source of oxygen-free environment, making storage safer.
iii. Sodium is relatively soft. It can be cut with a knife, and its hardness is comparable to a stick of butter. It can be deformed under pressure and shaped to various forms. However, sodium is highly reactive, which makes it prone to chemical reactions when exposed to moisture or air.