What is the formula for the cyanide ion?

The cyanide ion is represented by the formula CN(-). This indicates that it consists of one carbon atom (C) and one nitrogen atom (N), and it carries a negative charge. The negative charge comes from an extra electron that the cyanide ion has, making it a negatively charged anion.

In this case, the bonding occurs between the carbon and nitrogen atoms, where carbon forms a triple bond with nitrogen, giving it a linear structure. Understanding the structure helps to visualize how the atoms are combined and the charge distributed.

The other formulas do not accurately represent the cyanide ion. For example, the formula C(-) implies a single carbon atom with a negative charge but neglects the nitrogen that is essential to the cyanide ion. The formula CNO(-) represents a different ion known as the cyanate ion, while CN(2-) suggests a doubly charged cyanide ion, which does not exist in common chemistry. Therefore, the correct representation for the cyanide ion is CN(-).