Urea

(yoo-reah.) (Chem.) A normal constituent of urine. The quantity depends on the food consumed, and is connected with the amount of labor undergone. It may be produced artificially by evaporating down cyanate of ammonia, with which it is identical in composition, or it may be readily prepared from urine by dialysis. It crystallizes in long flattened prisms. It is very soluble in water and alcohol. When heated, it melts, and then decomposes. It forms salts with acids, the most characteristic being the nitrate and oxalate, which crystallize readily. Form. CoH4NO [s. 923]