Substance(A) in a group B of periodic table is yellowish-white delinquescent solid which sublimes.(A) dissolved in with water to form solution (B).a sample of (B) gave a white precipitate (C) on addition of dilute HNO3 and AGNO3 solution . precipitate (C) readily dissolved on the addition of dilute aqueous NH3, through gelatinous white precipitate (D) was formed In its place .(D) was filtered off and dissolved in excess NAOH , forming a clear solution (E), compound (D) was reprecipitate .(A) dissolved unchanged in dry ether,and when this solution was reacted with LIH one of two product (F) or g was formed , depending on whether the LIH one of two product (F)or(G) was formed , depending on whether the LIH was in excess or identity substance A to G.
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