How many electrons are there in n = 3(principle energy level) of the atom with atomic number 23

What is the most stable monatomic ion formed from nitrogen

Ajet plane is speeding down the runway during takeoff. air resistance is not negligible. identify the forces on the jet.

In a heat engine of 1000 j of heat enters the system and the piston does 500 j of work what is the final internal energy of the system if the inital energy was 2000 j we have to do all of these down here 1)write the equation 2)list out your know variables 3)plug the numbers into the equations 4)solve 5)write your solution statemtn that includes inital energuy and final energuy added