Several
1. The excess NaOH(aq) causes three of the cations to precipitate as hydroxides and three to form hydroxido complex ions.
2. In the presence of H2O2(aq), the cation in one of the insoluble hydroxides is oxidized from the +2 to the +3 oxidation state, and one of the hydroxido complex ions is also oxidized.
3. The three insoluble hydroxides are found as a dark precipitate.
4 The solution above the precipitate has a yellow color.
5. The dark precipitate from (3) reacts with HCL(aq), and all the cations return to solution one of the cations is reduced from the +3 to the +2 oxidation state.
6. The solution from (5) is treated with 6 MNH2(aq), and a precipitate containing one of the cations forms.
a.Write equations for the reactions referred to in item (1).
b. Write an equation for the most likely reaction in which a hydroxide precipitate is oxidized in item (2).
c. What is the ion responsible for the yellow color of the solution in item (4)? Write an equation for its formation.
d. Write equations for the dissolution of the precipitate and the reduction of the cation in item (5).
e Write an equation for the precipitate formation in item (6). [Hint You may need solubility product and complex-ion formation data from Appendix D, together with descriptive information from this chapter and from elsewhere in the text.]
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GENERAL CHEMISTRY(LL)-W/MASTERINGCHEM.
- 0.9563 g KHCO3 (M.r.(KHCO3) = 100.12 g/mol (mg/mmol)) have measured, and 50.0 cm3 stock solution have been prepared from it. 10.00 cm3 individual samples from it was titrated with HCl titrant in order to determine its concentration. The average HCl consumption was 19.18 cm3. The same HCl solution with were used to determine the concentration of NaOH titrant. The base consumption for 20.00 cm3 HCl was 21.35 cm3 NaOH. 1. concentration of HCl 2. concentration of NaOHarrow_forwardCan cadmium (II), and mercury (II) be separated quantitatively by precipitation as sulfides from a solution that is 0.15 M cadmium nitrate and 0.10 M in mercuric ions? If possible, what range of sulfide concentration is permissible? Do you expect any interference from the formation of hydroxides of both heavy metals? CdS (144.46); Ksp = 1.0 x 10 ^ -27HgS (232.66); Ksp = 2.0 x 10 ^ -53 HINT: Determine the concentration at which each of the cations start to precipitate out of solution. >Quantitative precipitation means 1/1000 remains in solution.arrow_forwardPlease help me out with making flowchart with thes steps. Write the result. Procedure 1. Place 20 drops of each of the following aqueous solutions to separate centrifuge tubes: 0.1M Cr (NO3)3, 0.1M Al (NO3)3, 0.1M Co (NO3)2, 0.1M Zn (NO3)2, 0.1M Mn (OH)2, 0.1M Ni (NO3)2, 0.1 M Fe (NO3)3. Make each solution basic by adding few drops of 6M NH4OH. Confirm using a litmus paper. 2. Add 5 drops of freshly prepared 6M (NH4)2S to each centrifuge tube. Place the samples in the centrifuge machine for 3 mins. After centrifuge record results. Decant the supernatant liquid of all the samples. 3. Add one drop of NH4OH in each centrifuge tubes. Add 20 drops of distilled water in each centrifuge tubes. Then add a few drops of 6M HCl in each solution. Place the samples in the water bath for 10 mins. After water bath, centrifuge the samples for 3 mins. 4. After centrifuge, add a few drops of 6M NH4Cl in each sample. Decant the supernatant liquid in each sample. 5. To the centrifuge containing…arrow_forward
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