1. الأستاذة\سارة البلوي

2. Part (1): Inorganic Qualitative Analysis When an acid, e.g. HCl is made to react with a base, e.g. NaOH, salt, NaCl, and water are formed according to the following equation : HCl + NaOH = NaCl + H2O acid base salt water The part of the salt which is derived from the base, Na+, is called the" basic radical",where as the other part which is derived from the acid is termed the" acidic radical". In the following labs we will describe the schemes of Qualitative Analysis of acid radicals or (anions) and basic radicals or( cations)

3. " basic radical 1)Dill. HCl group: 1)H2S (Acid medium dil. HCl). NH4OH in presence of NH4Cl H2S in the presence of NH4Cl and NH4OH (basic medium 1)(NH4)2CO3 in the presence of NH4Cl and NH4OH 1)No specific reagent

4. Group ІV: Ammonium Sulphide Group Nickel Ni +2 Cobalt Co +2 Manganese Mn +2 Zinc Zn +2 Gives a black ppt. of nickel sulphide NiS. NiCl 2 + H 2 S → NiS↓ + 2HCl Gives a black ppt. of cobalt sulphide CoS. Co(NO 3 ) 2 + H 2 S → CoS↓ + 2HNO 3 Gives a buff ppt. of manganese sulphide MnS. MnCl 2 + H 2 S → MnS↓ + 2HCl Gives a white ppt. of zinc sulphide ZnS. ZnSO 4 + H 2 S → ZnS↓ + H 2 SO 4 Salt solution + ammonium chloride(solid) (NH 4 Cl) + ammonium hydroxide solution (NH 4 OH) + hydrogen sulphide solution(H 2 S) To differentiate between Co +2 and Ni +2 Salt solution + dimethylglyoxime: Gives a red ppt. of nickel dimethylglyoxime. - ve

5. Group ІV: Ammonium Sulphide Group Nickel Ni +2 Cobalt Co +2 Manganese Mn +2 Zinc Zn +2 Gives a greenish ppt. of nickel hydroxide Ni(OH) 2 which is insoluble in excess of NaOH. A blue ppt. of basic cobalt salt appears which turns pink with heating in excess of NaOH due to the formation of cobaltous hydroxide. Co(NO 3 ) 2 + NaOH → Co(OH)NO 3 ↓ + NaNO 3 blue ppt. Co(OH)NO 3 + NaOH → Co(OH) 2 ↓ + NaNO 3 pink ppt. A white ppt. of manganous hydroxide Mn(OH) 2 is formed, which is insoluble in excess hydroxide. The ppt. rapidly changes into brown in the air, due to oxidation to manganic hydroxide Mn(OH) 3 MnCl 2 + 2NaOH → Mn(OH) 2 ↓ + 2NaCl 4Mn(OH) 2 + 2H 2 O + O 2 → 4Mn(OH) 3 Forms a white gelatinous ppt. of zinc hydroxide Zn(OH) 2 that is soluble in excess of NaOH Confirmatory tests: Salt solution+ sodium hydroxide solution (NaOH) Gives a greenish ppt. of Ni(OH) 2 which is soluble in excess of ammonia solution forming a blue solution of complex. Gives a blue ppt. of basic cobalt salt, Co(OH)NO 3, which dissolves in excess of ammonia solution. Partial precipitation of white Mn(OH) 2 becoming brown in air. Produces a white ppt. of Zn(OH) 2 which is soluble in excess of ammonia solution Salt solution+ ammonium hydroxide solution (NH 4 OH)

6. Group V: Ammonium Carbonate Group Barium Ba 2+ Strontium Sr 2+ Calsium Ca 2+ Gives whit ppt. of barium carbonate (BaCO 3 ). BaCl 2 +(NH 4 ) 2 CO 3 →BaCO 3 ↓+2NH 4 Cl ppt Gives whit ppt. of strontium carbonate (SrCO 3 ). SrCl 2 +(NH 4 ) 2 CO 3 →SrCO 3 ↓+2NH 4 Cl ppt Gives whit ppt. of calcium carbonate (CaCO 3 ). CaCl 2 +(NH 4 ) 2 CO 3 →CaCO 3 ↓+2NH 4 Cl ppt Salt solution+ NH 4 Cl (solid)+ NH4OH (solution) + Ammonium carbonate (NH 4 ) 2 CO 3 A white ppt. of barium sulphate (BaSO 4 ) is forme. Gives white ppt. of strontium sulphate (SrSO 4 ) on heating or after some time. No ppt. is formed. Confirmatory tests: Salt solution+ Calcium sulphate (CaSO 4 ) Gives a yellow ppt. of BaCrO 4, which is insoluble in acetic acid. Gives a yellow ppt. of SrCrO 4, which is soluble in acetic acid. No ppt. is formed from dilute solutions, however, from conc. Solutions a yellow ppt. of calcium chromate (CaCrO4), soluble in acetic acid, is produced. Salt solution + Potassium chromate solution (K 2 CrO 4 ) Imparts a pale apple green colour to the flame. Imparts a crimson red colour to the flame. Imparts a brick red colour to the flame. Flame test

7. Group VI Sodium Na + Potassium K + Magnesium Mg + Ammonium NH 4 + Flame test: Imparts a golden yellow colour to the flame. Salt solution + Tartaric acid solution: Gives white ppt. of potassium hydrogen tartarate from conc. Solutions. Salt solution + Sodium hydroxide solution (NaOH): Gives white ppt. of magnesium hydroxide (Mg(OH) 2 ). MgSO 4 + 2NaOH → Mg(OH) 2 ↓ + Na 2 SO 4 ppt. Salt solution + sodium hydroxide solution (NaOH): Ammonia gas is evolved (warm if necessary), ammonia can be recognized by its odour, by forming white fumes with conc. HCl on glass rod and by turning a red litmus paper oistended with water blue. NH 4 Cl + NaOH → NaCl + H 2 O + NH 3 --------------------------------Salt solution + Sodium cobaltinitrite (solid) (Na 3 (CO(NO 2 ) 6 ): Gives a yellow ppt. of potassium cobalnitrite K 3 (CO(NO 2 ) 6 ) Salt solution + Ammonium carbonate solution ((NH 4 ) 2 CO 3 ): Gives white ppt. of magnesium carbonate (MgCO 3 ) Salt solution + Nessler ˈ s reagent: Gives a brown ppt. or yellow colour even with very dilute solutions. --------------------------------Flame test: Imparts a violet colour (lilac) to the flame. Salt solution + Sodium phosphate solution: In presence of NH 4 Cl and NH 4 OH, it gives a white ppt. of magnesium ammonium phosphate (Mg(NH 4 )PO 4 ). Salt solution + Sodium cobaltinitrite (solid) (Na 3 (CO(NO 2 ) 6 ): Gives a yellow ppt. of ammonium cobaltinitrite ((NH 4 ) 3 (CO(NO 2 ) 6 ))