Q1: During conversion of ammonium carbamate into urea, presence of large excess of water

ANS:B - adversely affects the yield of urea.

During the conversion of ammonium carbamate into urea, the presence of a large excess of water does not affect the yield of urea. The conversion of ammonium carbamate to urea is typically carried out under high temperature and pressure conditions in the presence of excess water. The excess water helps in maintaining the reaction mixture in a liquid phase and facilitates the conversion of ammonium carbamate to urea. However, the excess water does not directly affect the yield of urea. The yield of urea is primarily determined by the extent of conversion of ammonium carbamate and the efficiency of the reaction conditions and catalysts used. Excess water mainly serves to provide the necessary conditions for the reaction to occur rather than directly influencing the yield of urea. Therefore, the presence of a large excess of water does not have a significant impact on the yield of urea.