How do the electron configuration of the calcium atom and the calcium ion different?

Answer 1

A calcium ion is Ca2+ and has 18 electrons and 20 protons. A calcium atom is Ca and has 20 electrons and 20 protons. So the ion has the same number of protons pulling a smaller number of electrons closer to the nucleus and so the ion is smaller.

Answer 2

the calcium atom has an atomic number of 20, so the configuration would be 1s^2 2s^2 2p^6 3s^2 3p^6 4s^2

however, calcium has a charge of 2+, which means it would lose 2 electrons, making the ion's number only 18, so the configuration would be 1s^2 2s^2 2p^6 3s^2 3p^6

Answer 3

When a negative ion is formed the extra electrons enter the outer valence shell- there is additional electron-electron repulsion which lowers the effetive nuclear charge experienced by the outer eletrons which causes the ion to be larger.

The above is simple ratioanlization-- atomic radii are not actually measured but "calculated"-- ionic radius is also difficult to measure- there is an assumption that ions are little spheres (this is often not the case) and actually published ionic radii are either a judgement made by looking at lots of different compounds or contain a measure of calculation as well.

Answer 4

The electron configuration of a neutral calcium atom is 1s2 2s2 2p6 3s2 3p6 4s2. When calcium forms an ion by losing two electrons, the electron configuration becomes 1s2 2s2 2p6 3s2 3p6, which is the electron configuration of argon. The calcium ion has a stable octet electronic configuration.

Answer 5

Na has 11 electrons in 3 shells

Ca has 20 electrons in 4 shells

Answer 6

The attraction between the positive nucleus and the negative electrons cloud is higher so the ionic radius decrease.