Q1: The number of kg vaporised per kg of steam fed to the evaporator is defined as

ANS:C - economy

Certainly! In the context of evaporators, "economy" refers to the efficiency of the evaporator in utilizing steam to vaporize water or other liquids. It is essentially a measure of how much vaporized liquid is produced per unit of steam input. The economy of an evaporator is typically expressed as the ratio of the mass of vaporized liquid produced to the mass of steam consumed. Mathematically, it can be represented as: Economy=Mass of vaporized liquid producedMass of steam consumedEconomy=Mass of steam consumedMass of vaporized liquid produced​ In other words, the economy tells us how many kilograms (or other appropriate units) of vaporized liquid are produced for each kilogram (or unit) of steam fed into the evaporator. A higher economy value indicates that the evaporator is more efficient in converting steam into vaporized liquid. This is desirable in industrial processes where steam is used as a heating medium and the goal is to maximize the production of vaporized liquid while minimizing steam consumption. Factors that can affect the economy of an evaporator include the design and operating conditions of the evaporator, such as the surface area available for heat transfer, the temperature and pressure of the steam, the temperature and flow rate of the liquid being evaporated, and any losses or inefficiencies in the system. In summary, economy is an important parameter in the design and operation of evaporators, as it provides a measure of the efficiency and effectiveness of the evaporator in vaporizing liquid using steam as a heating medium.