Be sure to answer all parts. One reason spectroscopists study excited states is to gain information about the energies of orbitals that are unoccupied in an atom's ground state. The following electron configuration represents an atom in an excited state. Identify the element and write its condensed ground-state configuration: 1s2 2s2 2p6 3s1 3p1

The element is magnesium

[Ne]3s2

Explanation:

When an atom is excited, electrons move from a lower to a higher energy level. These higher energy levels are called excited states. The ground state is the lowest energy arrangement of electrons.

Excited states are important in spectroscopy. It gives scientists an idea of the unoccupied orbitals in the ground state. This is easily deduced from the fact that the specie has twelve electrons in all.

Magnesium has ground state configuration as shown in the answer but has an excited state as shown in the question.

explanation:

let the different atoms be x and y. each with four protons and same mass will be represented as follows.

mass number is number of protons + number of neutrons.

            and  

since, it is given that one has a negative charge while the other is neutral. therefore, there will be increase in number of protons and the atom will be represented as follows.

according to periodic table, mass number of beryllium is 9 and it has atomic number 4 so, the atoms will be and .  

the protons and neutrons will be located inside the nucleus whereas the electrons will be revolving around the nucleus.  

it's c (engineer's do their work with mechanical stuff not on any living being)