The number of protons,neutrons and electrons in ${ }_{71}^{175} Lu$,respectively,are:

An element $M$ has an atomic mass $19$ and atomic number $9$. Its ion is represented by

Give the symbol of the following species:
$(i)$ Number of electrons,protons,and neutrons are $10, 8$,and $8$ respectively.
$(ii)$ $Ca$ $(Z = 20)$ and nucleon number $= 40$.
$(iii)$ Species with mass number $25$,protons $12$ (magnesium),and electrons $10$.
$(iv)$ Species of Bromine in which $(Z = 35)$,electrons $36$,and neutrons $45$.
$(v)$ $+2$ positive and $-2$ negative ions that are isoelectronic with $Al^{3+}$ $(Z = 13)$.

$A$ sodium cation $(Na^{+})$ has a different number of electrons from:

The expression $Ze$ gives :

The phosphide ion has an electronic structure similar to that of: