Which electron configuration represents an excited state for an atom for calcium

1. 2-8-7-1
2. 2-8-7-2
3. 2-8-7-3
4. 2-8-8-2

The electron configuration that represent an excited state for an atom of calcium is 2, 8, 7, 3.

Calcium atom has an atomic number of 20 and its electronic configuration is 2, 8, 8, 2. An atom is said to be in an excited state if it gains energy and move to an higher energy level. For the calcium atom given above, there are 20 electrons which are distributed into four shells. But in the excited state [option 3], one of the 8 electrons in the third shell gains energy and move to the fourth shell. Thus, the number of electrons in the third shell reduced by 1, while the number of electrons in the fourth shell increase by 1.

Electronic configuration is defined as the systematic distribution of electrons in the shells of atom. The excited state of electrons in calcium is 2, 8, 7, 3.

Calcium is a chemical element with symbol Ca and atomic number 20. The electronic configuration of calcium is 2, 8, 8, 2. The electrons are excited when an electron enters in the energy state higher than its ground state.

In calcium, the excited state of electronic configuration is 2, 8, 7, and 3. The electron in the M shell gets excited and enters in the N shell.

Therefore, the electronic configuration in excited state of calcium is 2, 8, 7, and 3.

To know more about electronic configuration, refer to the following link:

link

radioactive decay occurs in unstable atomic nuclei – that is, ones that don't have enough binding energy to hold

the nucleus together due to an excess of either protons or neutrons.

they it depends on if one believes about radioactivity, they make a geiger counter beep but maybe it was going to beep anyway electronics do wierd things all the time or it was programmed to beep near certain metals.