Systematic Analysis of Simple Salt 3

Made with help from nicholas roshan and Sugeeth Jayaraj Samala Augustine Created on 07-09-2023. Updated on 16-02-2024.

S.No	Experiment	Observations	Inference
1	Physical Examination: a) Noted the colour of the given salt b) Noted the smell of the salt	White No specific odour	C$Cu^{2+}$ M$Mn^{2+}$ F$Fe^{2+}$ N$Ni^{2+}$ F$Fe^{3+}$absent. N$NH_4^+$ S$S_2^-$and C$CH3COO^-$bsent
2	Dry Heated Test : Heated a pinch of the salt in a dry test tube and noted the observations a) Gas Evolved b) Sublimate formed c) Decrepitation d) Swelling e) Residue	No characteristic gas evolved No Sublimate No Decrepitation No Swelling Yellow when hot and white when cold	NO_3^$NO_3^-$2^$NO_2^-$3C$CH_3COO^-$4^$NH_4^+$-,$Cl^-$-,$Br^-$, $I^-$3^$SO_3^{2-}$3^$CO_3^{2-}$O$C_2O_4^{2-}$nt I^- ,$I^-$_4^$NH_4^+$nt Pb(NO$Pb(NO_3)_2$, NaCl absent. PO_4^$PO_4^{ 3-}$nt. Zn^{2$Zn^{2+}$be present
3.	Charcoal Cavity Test: Add Sodium carbonate ($Na_2CO_3$) to a part of the above salt. Place it in the charcoal cavity and moisten it. Direct the reducing flame towards it.	White Residue	S$Sr^{2+}$ Z$Zn^{2+}$ay be present.
4.	Cobalt Nitrate Test: To the above white residue added a drop of cobalt nitrate solution and heated	Green Residue	Z$Zn^{2+}$maybe present
5.	Flame Test : Prepared a paste of the salt in conc. HCl and performed flame test	Green flashes	Maybe Z$Zn^{2+}$present
6.	Dilute Sulphuric Acid Test: Treat a pinch of the salt with dil. H2SO4	No gas evolved	C$CO_3^{2-}$ S$S^{2-}$ S$SO_3^{2-}$ N$NO_2^-$absent
7.	$KMnO_4$ Test : To a pinch of the salt added dil. $H_2SO_4$, boil off any gas released. Add$KMnO_4$ solution dropwise.	Pink colour of K$KMnO_4$not discharged	C$Cl^-$ B$Br^-$ I$I^-$ C$C_2O_4^{ 2-}$and F$Fe_{2+}$maybe absent
8.	Conc. Sulphuric Acid Test: Heated a pinch of the salt with conc. sulphuric acid and added to it a paper pellet.	No gas/vapours evolved	C$Cl^-$ B$Br^-$ I$I^-$ C$C_2O_4^{ 2-}$N$NO_3^-$C$CH_3COO^-$absent

9.	Sodium Carbonate extract: A pinch of salt is mixed with double the mount of Sodium Carbonate in a test tube and is boiled with 10-15 mL of distilled water for some time. The suspension obtained is filtered. This filtrate is called sodium carbonate extract.

10.	Confirmatory test for individual radicals: a) Barium chloride test: To a part of the aqueous solution of salt add barium chloride solution. (b) Match stick test: Filter the above white ppt. and mix it with sodium carbonate and a little powdered charcoal so as to get a paste. Take some of this paste on one end of a wooden splinter and heat it in the reducing flame till the mass fuses. Dip the fused mass into sodium nitroprusside solution taken in a china dish.	White ppt evolved. Violet streaks are produced	SO$SO_4^{2-}$onfirmed SO$SO_4^{2-}$onfirmed

11.	Preparation of original solution (O.S) To a small quantity of given salt, add some distilled water, shake it well. The contents dissolve, the clear solution thus obtained is labelled as the original solution (O.S.), where the contents is the salt given.
12.	Group Separation: a) Group 0: the solid salt is heated with concentrated $NaOH$solution b) Group 1:Dilute $HCl$is added to OS c) Group 2: To dilute HCL and original solution add yellow ammonium sulphide $(NH_4)_2S$ d) Group 3: To 5 mL of O.S., add 4-5 mL of conc. $HNO_3$acid, boil it. Add solid 2g of$NH_4Cl$ and cool solution under tap water. Add excess of $NH_4OH$ and shake. e) Group 4: To O.S., add $NH_4Cl$ , $NH_4OH$ and yellow ammonium sulphide.	no characteristic ammonia smell No PPT No black PPT No PPT No ppt.	Group 0 Absent Group 1 absent. Group 2 absent Group 3 absent Group 4 present. (Maybe Fe$Fe^{2+}$Fe$Fe^{3+}$Zn$Zn^{2+}$

13.	Confirmatory tests:- By taking the preliminary tests as a starting point, let us start with the confirmatory test for zinc. Dissolve the ppt. in dil. HCl, boil off the (NH_4)_2 i) NaOH test:- To the first part of the solution, add a few drops of $K_2CrO_4$solution. ii) Potassium ferrocyanide test: To another part of the sol., add $K_4[Fe(CN)_6)]$soln.	White ppt. White or bluish ppt.	Zn^{2+} con$Zn^{2+}$ Zn^{2+} con$Zn^{2+}$

Result

• The acidic radical of the given salt is sulphate($SO_4^{2-}$).

• The basic radical of the given salt is Zinc ($Zn^{2+}$).

• The given salt is Zinc Sulphate ($Zn(SO_4)$).