i) In solvent extraction of trace metal ions, chelating agent should contains large number of resonating structures. ii) Solvent used in solvent extraction should be non-viscous and has high boiling point. 2. A 95% of nickel (II) - dimethylglyoximate chelate is extracted into chloroform ( 5mL ) when 100mL of water sample containing nickel (II) adjusted to pH 5-6 was shaken for 5min at room temperature. Calculate the distribution ratio, D, the concentration of nickel remained in ppm(g/mL) and what will be the extraction percentage if the chloroform volume is tripled. 1. A. 1.5g alloy sample of steel was dissolved in nitric acid, treated with an excess of potassium periodate, and heated to oxidize any manganese present to the +7 state i.e. to permanganate ions. The reaction proceeds as follows: 5IO4+Mn2++3H2O2MnO4+5IO3+6H+ The resulting solution was diluted to 100mL in a calibrated volumetric flask. Color match was achieved between the diluted solution and a 5104M of KMNO4 solution when the light path through the standard was 2cm and that through the sample solution was 1.0cm Calculate the manganese content in terms of percentage (%) and ppm(g/mL) units. 2. Sketch the photometric titration curve for the reaction of Fe3+(100mL, colorless, 10ppm) with excess KCNS (0.1%, Colorless) in acid media. The reaction between Fe3+ and KCNS proceeds according to the following equation: Fe3++nCNS+3H2O[Fe(CNS)n]3n