Provide the symbol,name,atomic number $(Z)$,mass number $(A)$,and the number of electrons $(e)$,protons $(p)$,and neutrons $(n)$ for elements with atomic numbers $1$ to $10$.

What do you understand by isoelectronic species? Name a species that will be isoelectronic with each of the following atoms or ions.
$(i)$ $F^{-}$
$(ii)$ $Ar$
$(iii)$ $Mg^{2+}$
$(iv)$ $Rb^{+}$

Which of the following properties are different for neutral atoms of isotopes of the same element?

Find the number of neutrons,electrons,and protons in the following species:
$(i)$ $_{15}^{31}P$
$(ii)$ $_{11}^{23}Na^{+}$
$(iii)$ $_{16}^{32}S^{2-}$
$(iv)$ $_{101}^{235}X$
$(v)$ $_{20}^{40}Ca^{2+}$
$(vi)$ $_9^{19}F^{-}$

Match the following species with their respective number of electrons:
| Species | Number of electrons |
| :--- | :--- |
| $(a)$ $O^{2-}$ | $(i)$ $18$ |
| $(b)$ $Li^{2+}$ | (ii) $2$ |
| $(c)$ $He$ | (iii) $10$ |
| $(d)$ $Ca^{2+}$ | (iv) $1$ |

Which of the following statements is false?