91Ó°ÊÓ

What are the condensed electron configurations of \(\mathrm{K}, \mathrm{K}^{+}\) \(\mathrm{Ba}, \mathrm{Ti}^{4+}\) and \(\mathrm{Ni} ?\)

How many unpaired electrons are there in the following ground-state atoms and ions? (a) \(\mathrm{N} ;\) (b) \(\mathrm{O} ;\) (c) \(\mathrm{P}^{3-} ;\) (d) \(\mathrm{Na}^{+}\).

How many unpaired electrons are there in the following ground-state atoms and ions? (a) Mn; (b) \(\mathrm{Ag}^{+} ;\) (c) \(\mathrm{Cu}^{3+}\) (d) \(\mathrm{Ti}^{2+}\)

Identify the element whose condensed electron configuration is \([\mathrm{Ne}] 3 s^{2} 3 p^{3} .\) How many unpaired electrons are there in the ground state of this atom?

Which monatomic ion has a charge of \(1-\) and the condensed electron configuration \([\mathrm{Ne}] 3 s^{2} 3 p^{6} ?\) How many unpaired electrons are there in the ground state of this ion?

Which monatomic ion has a charge of \(1+\) and the electron configuration \([\mathrm{Kr}] 4 d^{10} 5 s^{2} ?\) How many unpaired clectrons are there in the ground state of this ion?

Which of the following electron configurations represent an excited state? a. \([\mathrm{He}] 2 s^{1} 2 p^{5}\) b. \(\left[\mathrm{K}_{\mathrm{r}}\right] 4 d^{10} 5 s^{2} 5 p^{1}\) c. \([\mathrm{Ar}] 3 d^{10} 4 s^{2} 4 p^{5}\) d. \([\mathrm{Ne}] 3 s^{2} 3 p^{2} 4 s^{1}\)

Which of the following condensed clectron configurations represent an excited state? Could any represent ground-state clectron configurations of \(2+\) ions? a. \([\mathrm{Ar}] 4 s^{2} 4 p^{1}\) b. \([\mathrm{Ar}] 3 d^{10}\) c. \([\mathrm{Kr}] 4 d^{10} 5 s^{1}\) d. \([\mathrm{Ar}] 3 s^{2} 3 p^{6} 3 d^{1}\)

In which subshell are the highest-energy electrons in a ground-state atom of the isotope \(^{131}\) I? Are the electron configurations of \(^{131} \mathrm{I}\) and \(^{127} \mathrm{I}\) the same?

No known element contains electrons in an \(\ell=4\) subshell in the ground state. If such an element were synthesized, what is the minimum atomic number it would have to have?