Chemistry Question from JEE Main 2026 · 28 January, Shift 2

The number of isoelectronic species among $\ce{Sc^{3+}}, \ce{Cr^{2+}}, \ce{Mn^{3+}}, \ce{Co^{3+}}$ and $\ce{Fe^{3+}}$ is ‘$n$’. If ‘$n$’ moles of AgCl is formed during the reaction of complex with formula $\ce{CoCl3(en)2NH3}$ with excess of AgNO$_3$ solution, then the number of electrons present in the $t_{2g}$ orbital of the complex is _____.