The substance to be analyzed – is deep-pink colored, highly soluble in water salt. Reaction with NH; gives blue-colored precipitate, which can be dissolved in NH3 surplus accompanied by dirty-yellow colored solution formation. After precipitation of cation by "sodium carbonate drawing out" method, supernatant was independently treated by silver nitrate solution and barium chloride solution (in acid medium in both cases) – any precipitation hasn't been observed. Addition of antipyrin in acid medium changes color to red. What kind of substance is this? Co(NO3)2 CuCl, Co(CH;COO), FeSO4

The substance to be analyzed – is deep-pink colored, highly soluble in water salt. Reaction with NH; gives blue-colored precipitate, which can be dissolved in NH3 surplus accompanied by dirty-yellow colored solution formation. After precipitation of cation by "sodium carbonate drawing out" method, supernatant was independently treated by silver nitrate solution and barium chloride solution (in acid medium in both cases) – any precipitation hasn't been observed. Addition of antipyrin in acid medium changes color to red. What kind of substance is this? Co(NO3)2 CuCl, Co(CH;COO), FeSO4

EBK A SMALL SCALE APPROACH TO ORGANIC L

4th Edition

ISBN:9781305446021

Author:Lampman

Publisher:Lampman

Chapter80: Crystallization: Purification Of Solids

Section: Chapter Questions

Problem 3P

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xpress numerical result with an accuracy of: Х,Х 1. The substance to be analyzed – is deep-pink colored, highly soluble in water salt. Reaction with NH3 gives blue-colored precipitate, which can be dissolved in NH3 surplus accompanied by dirty-yellow colored solution formation. After precipitation of cation by “sodium carbonate drawing out” method, supernatant was independently treated by silver nitrate solution and barium chloride solution (in acid medium in both cases) – any precipitation hasn`t been observed. Addition of antipyrin in acid medium changes color to red. What kind of substance is this? Explain you answer, provide chemical equations
Briefly describe mechanism involve during formation of precipitate.
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In this activity, you will develop an experimental procedure to solve a problem. Consider the followingscenario:You are the manager of a chemical stockroom, and find a bottle containing approximately one liter of aclear and colorless solution of unknown identity and concentration. Your only clue to its identity is thatit was found between bottles of silver fluoride and sodium fluoride, so it is likely an aqueous solution ofone of those two compounds. You will need to develop a procedure to determine the following:a) The identity of the unknown solutionb) The concentration of the unknown solutionWrite out a precise procedure, which includes all glassware, reagents, and steps. You will also need towrite the calculations that you would need to determine the concentration of the solution. Assume thatyou have access to any reagent you might need
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Caustic potash that has been exposed to air is found on analysis to contain 90.00% KOH, 2.38% K2CO3 and 7.62% H2O. What weight of residue will be obtained if 1.00 g of this sample is added to 46.00 mL of 1.00 N HCl and the resulting solution, after neutralization with 1.070N KOH is evaporated to dryness?