Question

The dazzling colors produced by fireworks result from excited gaseous atoms or molecules emitting light. The normal electron configuration of an atom is known as the

"ground state." In ground state all electrons are in the lowest energy levels available. When atoms or ions are heated, some electrons may absorb enough energy to
allow them to "jump" to higher energy levels. The atom or ion is then said to be in the "excited state." The electrons cannot remain in this excited state for long and will
emit energy in the form of light when they return to ground state. It is this light we see when an atom is heated in a flame. The frequency or color of light emitted
depends on the energy difference between the excited state and the ground state.
Chose the correct ground state configuration for Sr


1s22s22p63s23p64s23d104p65s2


1s22s22p63s23p64s23d104p8


1s22s22p63s23p64s23d104p75s1


1s22s22p63s23p64s24p64d105s2

Answer 1

The ground state electron configuration of Sr (Strontium) is 1s22s22p63s23p64s23d104p65s2. This means that the electrons in the Sr atom occupy the lowest possible energy levels available to them. The electron configuration is written as a series of numbers and letters that indicate the number of electrons in each orbital. In this case, the first electron goes in the 1s orbital, the next two electrons go in the 2s orbital, the next six electrons go in the 2p orbital, the next six electrons go in the 3s orbital, the next six electrons go in the 3p orbital, the next ten electrons go in the 4s orbital, and the final two electrons go in the 5s orbital. When Sr is heated and its electrons are excited, they absorb enough energy to jump to higher energy levels. When these electrons then return to the ground state, they emit light of a specific frequency or color.