JAMB - Chemistry (1985 - No. 21)
The atomic number of an element whose cation, X2+, has the ground state electronic configuration 1s22s22p63s22p6 is?
16
18
20
22
24
Giải thích
-The main difference between ground state and excited state is that ground state is a state where electrons in a system are in the lowest possible energy levels whereas excited state is any state of the system that has a higher energy than the ground state.
-Calcium atoms have 20 electrons and the shell structure is 2.8. 8.2. The ground state electron configuration of ground state gaseous neutral calcium is [Ar]