Urea can react with acid to form salt. There is hydrolysis. Condensation can be performed at high temperatures to produce biuret, triuret and cyanic acid. Heating to 160℃ decomposition, producing ammonia gas and isocyanic acid. Because this substance is found in human urine, it is named urea. Urea contains 46% nitrogen (N), which is the highest nitrogen content Z among solid nitrogen fertilizers.