Which of these elements has two valence electrons? hydrogen (h) barium (ba) nitrogen (n) krypton (kr) bromine (br)

What is the independent variable in this investigation? mass volume sample number substance density

Explain in detail of the four major scientific developments that spurred the formulation of the plate tectonics theory

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