The arrangement within energy levels of the seven electrons of an atom of nitrogen is 2.5 (that is the first sub shell= 2 while the second sub shell=5)
explanation
In every atom the first energy level can accommodate a maximum of two (2) electrons. The next energy level can accommodate a maximum of 8 electrons. Therefore the seven electron for nitrogen, 2 electron are put on first sub shell while other other 5 are putted in the second sub shell.
