A composite plane wall consists of a 12-in.-thick layer of insulating concrete block (kc 5 0.27 Btu/h ft 8R) and a 0.625-in.-thick layer of gypsum board (kb 5 1.11 Btu/h ft 8R). The outer surface temperature of the concrete block and gypsum board are 4608R and 5608R, respectively, and there is perfect contact at the interface between the two layers. Determine at steady state the instantaneous rate of heat transfer, in Btu/h per ft2 of surface area, and the temperature, in 8R, at the interface between the concrete block and gypsum board. 2.
WEEK OF 4/4 – 4/8 NOTES IONIZATION ENERGY Ionization Energy – closely related to effective nuclear charge, energy when one mol of electron is removed by a gas, forming a cation - INCREASES across a period - DECREASES down a group o Because of shielding on the outer e-, more shielding means easier to pluck an electron off IE1 < IE2