Sn/HCl\mathrm{Sn} / \mathrm{HCl}Sn/HCl
Conc. HNO3\text { Conc. } \mathrm{HNO}_{3} Conc. HNO3
অনার্দ্র AlCl3\mathrm{AlCl}_{3}AlCl3
Na /ether \mathrm{Na} \text { /ether }Na /ether