Questions in atomic-structure

Select	Question
	The mass number of an anion,${X^{3 - }}$,is $14$. If there are ten electrons in the anion,the number of neutrons in the nucleus of atom,${X_2}$ of the element will be
	Which of the following are isoelectronic species $I = CH_3^ +,\,II - N{H_2},\,III - NH_4^ +,\,IV - N{H_3}$
	The charge on the atom containing $17$ protons,$18$ neutrons and $18$ electrons is
	Number of unpaired electrons in inert gas is
	In neutral atom,which particles are equivalent
	Nuclei tend to have more neutrons than protons at high mass numbers because
	Which one of the following is not isoelectronic with ${O^{2 - }}$
	The number of electrons in ${[_{19}^{40}K]^{ - 1}}$ is
	The number of electrons and neutrons of an element is $18$ and $20$ respectively. Its mass number is
	Number of protons,neutrons and electrons in the element $_{89}^{231}Y$ is