225) The transfer of heat by molecular collision is smallest in

226) During dehumidification process, the relative humidity

227) The space between the two walls of a thermos flask is evacuated because vacuum is a __________ conductor of heat.

228) The ratio of actual heat transfer to the maximum possible heat transfer is known as heat exchanger effectiveness.

229) When the discharge pressure is too high in a refrigeration system, high pressure control is installed to stop the compressor.