Which of the following elements in their respective oxidation states does not develop spin only magnetic moment? [$$\mathrm{Ti}(\mathrm{Z}=22), \mathrm{Zn}(\mathrm{Z}=30), \mathrm{V}(\mathrm{Z}=23), \mathrm{Cu}(\mathrm{Z}=29)$$]

What is IUPAC name of $$[\mathrm{Co}(\mathrm{H}_2 \mathrm{O})(\mathrm{NH}_3)_5] \mathrm{I}_3$$ ?

What is effective atomic number of $$\mathrm{Pt}$$ in $$\left[\mathrm{Pt}\left(\mathrm{NH}_3\right)_4\right]^{2+}$$ ? (Given atomic number of $$\mathrm{Pt}=78$$)

Which among following compounds is a secondary amine?