The reaction between urea and nitric acid is a classic example of the formation of a salt, namely, urea nitrate. The reaction can be represented as follows:

CO(NH2)2 + 2HNO3 → CO(NH2)2·2HNO3

In this reaction, urea acts as a base and nitric acid acts as an acid. The product of the reaction is urea nitrate, which is a salt that contains the urea cation and the nitrate anion. Urea nitrate is a white, crystalline solid that is highly soluble in water. It is commonly used as a fertilizer due to its high nitrogen content.

The reaction between urea and nitric acid is a relatively simple one and can be easily carried out in a laboratory setting. To perform the reaction, simply mix together equal volumes of urea and nitric acid in a beaker. The reaction will occur immediately and the urea nitrate will begin to precipitate out of the solution. The precipitate can be filtered and dried to obtain the pure urea nitrate salt.

The reaction between urea and nitric acid is an important one because it demonstrates the basic properties of urea. Urea is a versatile compound that can react with a variety of other compounds to form different products. This makes urea a valuable starting material for the synthesis of a wide range of compounds, including fertilizers, pharmaceuticals, and plastics.