Question

hexahydrate 3. A lab student analyzed her nickel-en complex for ethylenediamine, en, content. A 0.579 g sample of the synthesized Ni-en complex was dissolved in about 50 mL of water and titrated with 0.181 M HCl (ag). Endpoint required 38.02 mL of the HCl (ag). What is the mass (in grams) of en in the Ni-en complex analyzed? a. 0.153 g b. 0.207 g c. 0.413 g d. 0.104 g e. 0.199 g 4. Continuing on with the analysis of the Ni-en complex as found in question #3, 40 mL of dimethylglyoxime, DMG, solution was added to the titrated nickel-en complex solution. The resulting beautiful red complex, Ni(DMG)2 was collected by filtration and found to weigh 0.443 g. What is the mass (in grams) of Ni in the Ni-en complex analyzed? a. 0.180 b. 0.045 d. 2.18 g d. 0.0900 g e. 1.45 g 5. Determine the empirical formula of the complex synthesized in questions #3 and #4 above. e. [Ni(en)]SO4-4H20 a. [Ni(en) (H20)s]SO4 d. [Ni(en)]SO4.4H20 b. [Ni(en)2]SO4 · 5H20 c. [Ni(en)2(H20)2]SO4 · 3H20 Ni-en complex F19 Pr GOD F4

Answer 1

3) Ni-en: 0.579g Titrated with O. IBIM HCL 138.02mL 38.02 ml x 0,181 mol K = 6.88162 mmol. Ha Ni-en + 200 Nich2 - + en This signifies that 2 mol of a react with 1 mol of en. → 6.88162 no ci- 6.88162 mol en moles den 3.44081 mmo mass = mdar mass x moles = Gog mot! x 3.44081 mayo = 206.499 mg ("imdar mass on 60 g/mol) & 1000 mg = 1g mass ofen = 0.207g6w 4) Nici +2D MG NI (DNG) +20% molar mass N; (OMG)₂ = 288.9 glmol motor mass of Ni = 58.7 g/mol mass Ni BMG)2 = 0.443g :: 288.9g of Ni(MG), Contain 58.7 g Ni 10.443g " " "58. 7 of x0.4439 Mass Ny = 0.09g | @w