Which would react chemically by forming an ionic bond?
a. 2 chlorine atoms with 7 valence electrons each
b. 1 neon atom with 8 valence electrons and 1 lithium atom with 1 valence electron
c. 1 sodium atom with 1 valence electron and 1 chlorine atom with 7 valence electrons
d. 2 hydrogen atoms with 1 valence electron each and 1 oxygen atom with 6 valence electrons

Air enters a gas turbine with two stages of compression and two stages of expansion at 100 kpa and 17°c. this system uses a regenerator as well as reheating and intercooling – the intercooler returns the air to the inlet temperature. the pressure ratio across each compressor is 4 ; 300 kj/kg of heat are added to the air in each combustion chamber; and the regenerator operates perfectly while increasing the temperature of the cold air by 20°c. determine the system’s thermal efficiency. assume isentropic operations for all compressor and the turbine stages and use constant specific heats at room temperature. (0.378)