give the conjugate base for HNO2

If HX is an acid, X- is its conjugate base.

So, HNO2 has as its conjugate base NO2-

To determine the conjugate base of HNO2, we first need to identify the acid. In this case, HNO2 is an acid, so its conjugate base will be formed when it loses a hydrogen ion (H+).

The formula for HNO2 is nitrous acid. When nitrous acid loses a hydrogen ion, it forms the conjugate base, which is called nitrite ion (NO2-). Hence, the conjugate base for HNO2 is NO2-.