When metal 'M' is treated with NaOH, a white gelatinous precipitate 'X' is obtained,

When metal 'M' is treated with NaOH, a white gelatinous precipitate 'X' is obtained, which

is soluble in excess of NaOH. Compound 'X' when heated strongly gives an oxide which is

used in chromatography as an adsorbent. The metal 'M' is