* Fixed Ratio: A compound always has a fixed ratio of its constituent elements. In NaCl, the ratio of sodium to chlorine is always 1:1. This means every molecule of sodium chloride will contain one sodium atom and one chlorine atom.
* Chemical Reaction: Sodium chloride is formed by a chemical reaction between sodium and chlorine. This reaction involves the transfer of electrons between the sodium and chlorine atoms, resulting in the formation of ionic bonds. This chemical reaction completely changes the properties of the original elements.
* New Properties: The properties of sodium chloride are entirely different from those of its constituent elements. Sodium is a highly reactive metal, and chlorine is a toxic gas. Sodium chloride is a stable, white solid, and is safe for consumption in moderate amounts.
* Uniformity: Sodium chloride is a homogeneous substance, meaning it has a uniform composition throughout. This is unlike a mixture, which can have varying compositions.
In contrast to a mixture:
* Mixtures can have varying proportions of their components.
* Mixtures are formed by physical processes, like mixing sand and sugar, and the components retain their individual properties.
In summary: Sodium chloride is a compound because it is formed by a chemical reaction, has a fixed ratio of elements, and exhibits entirely new properties compared to its constituent elements.
