Q1.You are given a 2.198g sample containing a mixture of XO and X2O3. It requires 0.015 mole of K2Cr2O7 to oxidise the given sample completely to XO4- and Cr3+. If 0.0187 mole of X04- is formed , what is the atomic mass of X.Q2. Calculate the amount of SeO3 2- in solution on the basis of following data , 20 ml of M/60 solution of KBrO3 was added to definite volume of SeO3 2- solution. The bromine evolved was removed by boiling and excess of KBrO3 was back titrated with 5.1 ml of M/25 solution of NaAsO2. The reactions are given below.a. SeO3 2- + BrO3- + H+ gives SeO4 2- + Br2 + H20 b. BrO3 - +AsO2- + H20 gives Br- + AsO4 3- + H+Atomic weight of As = 75 of Se = 79 and of Br = 80

muktesh singh , 9 Years ago

Grade 11