before coming to lab outline here the steps you plan to use to analyze your five

Question

before coming to lab outline here the steps you plan to use to analyze your five solutions. We will be given an 5 test tubes each containing a solution of an unkown compound.

5 Solution analysis (Only 1 will be present in each group)

Acid- HCl, HNO3, H2SO4

Base - NaOH, NH3, Na2S

Chloride Salt - NaCl, BaCl2, CuCl

Nitrate Salt - AgNO3, Cu(NO3)2, Fe(NO3)3(this will appear acidic)

Sodium Salt - NaI, Na2SO4, Na2CO3(this will appear basic)

Let me know if you need more info.

Edit: So, what needs to be done is being able to determine which of the 3 compounds are in each group. there will only be 1 in each group. so far i have done a bit to help to isolate them

Colored Ions
Cu - Blue

Fe - Yellow

Ni - Green

Co - Pink

Cr - Blue - Violet

Observations, Odor, and Ph

1. Observe solutions and separate by color and smell.

2. Do a Ph test. Red paper to test for base, Blue to test for acid. Fe(NO3)3 will appear acidic, and Na2CO3 will appear basic.

General test to determine Group I and II anions

Group I- to 10 drops of unknown, add 6 M NH3 until basic and then 4 drops BaCl2 solution. Formation of a PPT confirms presence of SO4, CO3, or PO4

Group II- to 10 drops of unknown, add 6 M HNO3 until acidic then add 4 drops more. Add 3 drops AgNO3 solution. Formation of a PPT confirms the presence of Cl, Br or I

Possible Group 1 unknowns- H2SO4, Na2SO4, Na2CO3

Possible Group 2 unknowns- HCl, Chloride Salts, NaI

Explanation / Answer

Solution 1) When AgNO3 solution is added to unknown acid solution and the resultant solution is clear then the given acid is HNO3. This is due to common ion effect. HCl and H2SO4 will give white precipitate of AgCl and Ag2SO4, respectively. When BaCl2 solution is added to unknown acid solution and the resultant solution is clear then the given acid is HCl. Again due to common ion effect. H2SO4 will give white precipitate of BaSO4.

Note, most sulfates are soluble with the exception of BaSO4, Ag2SO4, PbSO4 and SrSO4 (from the solubility chart). Also, most halides are soluble with the exception of AgCl, PbCl2 (in dilute acids) and Hg2Cl2 are all insoluble. Hence, you can replace BaCl2 solution with SrCl2.

Solution 2) NaOH and NH3 are bases and will turn red litmus to blue while Na2S is a salt and the red litmus will remain red. It reacts with acid to produce H2S gas which smells like rotten egg. NH3 has a distinctive odour you cannot miss, very strong and pungent. Thus you can differentiate between these three solutions.

Solution 3) NaCl and BaCl2 solutions are clear while CuCl2 is blue-green. If the solution is clear, and you add few drops of H2SO4, then BaCl2 will give white precipitate of BaSO4 while Na2SO4 being soluble in water will result in clear solution.

Solution 4) AgNO3 is colourless, Cu(NO3)2 is blue in colour while Fe(NO3)3 is yellow in colour. Thus we can identify these salts by its appearance.

Solution 5) Na2CO3 reacts with acid to give bubbles of CO2 while no CO2 gas is produced when NaI and Na2SO4 are reacted with acid. When Ba(NO)3 solution is mixed with the unknown solution and there is no precipitate. This indicates the presence of NaI for BaI2 is soluble salt. Precipitate of BaSO4 and BaCO3 is formed when Na2SO4 and Na2CO3, respectively are employed.

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