Please help me guysMendeleev classified the elements and arranged them in the form of table.Hydrogen which resembles alkali metal and halogen,was placed along with the alkali metals in the first group. why how does it resembles halogen why do you think he named it as periodic table
Answers
Actually Hydrogen doesn’t have a fixed position in the periodic table. In some tables it is placed with alkali metals(above Sodium) and in some others it is lonely placed at the top (Randomly, Just above 1st Period).
Hydrogen resembles alkali metals in electronic configuration. Hydrogen atom has the e- configuration 1s1 and is the first element to be placed as per the rule. It is placed with alkali metals because it can loose its one e- to form H+ just like the alkali metals.
but hydrogen also resembles halogens. Alkali metals form hydrides like NaH and LiH just similar to NaCl and LiCl. Electrolysis of hydrides gives H2 and Electrolysis of NaCl yields Cl2. Hydrogen can gain one electron like halogens to form noble gas configuration (H-).
Due to its resemblence with alkali metals and halogens, its position is not yet fixed. But coventionally we keep it along with the alkali metals.
