Question

name the basic radicals present in group3, group3A,group4, and group 5

Answer 1

SEMI – MICRO QUALITATIVE ANALYSIS OF SIMPLE INORGANIC SALT ... INFERENCE INFERENCE 2nd group Acid radical is present The Acid radical may be Cl-. SECOND .... Part (2) + 5 drops of dimethyl glyaxime reagent + NH4OH.

Answer 2

Explanation:

Group IIIa : The hydroxides of Al3+, Cr3+ and Fe3+ are treated with NaOH and Na2O2 or H2O2 when Fe(OH)3 remains as precipitate and Al3+ and Cr3+ goes in solution. If Cr3+ is present the solution turns yellow and will give precipitate of PbCrO4 in presence of acetic acid. Fe3+ and Al3+ are tested separately.

Group IV : The carbonates of this group are dissolved in acetic acid and treated with a little K2CrO4 solution, when yellow BaCrO4 precipitates and filtrate is treated with ammonium sulphate solution where SrSO4 precipitates and calcium sulphate goes in solution forming a complex. These three radicals thus can be individually tested. They can also be confirmed by the flame test.

Group V : The only radical precipitated is magnesium as magnesium phosphate. A small portion from the filtrate of fourth group is tested and if magnesium is present the remaining filtrate is heated to dryness and the dry residue is dissolved in a small portion of HCl and the radicals Mg2+, Na+ and K+ are tested in the presence of each other. Na+ and K+ can be confirmed by flame test.