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What are the Group 5 cations?

What are the Group 5 cations?

Group 5 cations are magnesium (II) Mg2+, potassium (I) K+ and sodium (I) Na+. These cations do not react with hydrochloric acid HCl, hydrogen sulphide H2S, ammonium sulphide and ammonium carbonate (NH4)2CO3.

What is the group reagent for Group 5?

Ammonium sulphide is used for testing 5th group cations.

What are the Group I cations?

Group I Cations (Ag+, Hg22+ and Pb2+ – insoluble chlorides): Among the common metallic cations only three cations form insoluble chlorides with hydrochloric acid. When 6M of HCl is added to the solution, white precipitates of AgCl, Hg2Cl2 and PbCl2 are formed. Other metallic cations remain in solution.

How are cations classified into groups?

These cations are divided into five groups based on their reactions with the Cl−, S2-, OH−, and CO32- ions: The group reagents for Groups II to IV precipitate all of the members of each of the preceding groups as well as the members of their own groups.

What are Group 2 cations?

Group II (Cu2+, Bi3+, Cd2+, Hg2+, As3+, Sb3+, Sn4+) cations produce very insoluble sulfides (Ksp values less than 10-30) so they can be precipitated by low amounts of sulfide ion; this can be achieved by adding an acidic solution of H2S.

What are the group reagent of group 6?

Salt Analysis of Cations and Anions

Group Group Reagent Radicals
III Group O.S. +NH4Cl + NH4OH AI2+ ,Fe3+
IV Group O.S. + NH4CI + NH4OH +H2S Ni2+ ,Mn2+ , Zn2+ ,Co2+
V Group O.S. + NH4CI + NH4OH +(NH4)2CO3 Ba2+, Ca3+, Sr2+
VI Group O.S + NH4CI + NH4OH + NaH2PO4 Mg2+

Why salts are classified into groups?

Salts can be acidic, basic, or neutral. Acidic salts are formed when a strong acid reacts with a weak base. Basic salts are formed when a strong base reacts with a weak acid. When a strong acid reacts with a strong base, neutral salts are formed.

Why do we add NH4OH in Group 4 of mixture analysis?

The solubility product of group IV radicals is greater than that of group II ions. the removal of H⊕ ion causes more H2S to dissociate or ionise, thus increasing the concentration of S- ions so the product [M2+][S2-] exceeds the solubility products of the sulphides of Zn, Mn, Ni and Co and hence they are precipitated.

Are Group 2 cations acidic or basic?

If not, don’t be scared, we prepared this summary for you! Group 2 consists of those cations who precipitate as sulphides around pH 0-2. The precipitating reagent is sodium sulphide Na2S. The solution is acidic because of hydrochloric acid; it corresponds to the supernatant coming from the analysis of group 1 cations.

What is group reagent in Group 4?

Fourth group- Fourth group cations are Ni2+,Co2+,Mn2+,Zn2+ and the group reagent is Hydrogen Sulphide (H2S) in presence of NH4OH .

How are Group IV cations similar to Group 1 cations?

Group IV Cations (Ca2+, Sr2+and Ba2+– carbonate precipitates): These three metallic cations all belong to Group IIA in the periodic table of elements and therefore their chemical properties are very similar. They form soluble chlorides and sulfides and hence are separable from group 1, 2 and 3 cations.

How to analyze cation Group 5 in lu le laboratory?

Divide the solution into three equal parts. Add some drops uranyl magnesium acetate in to one part of the sample which is without ammonium. Wait the reaction for 5 minutes. Five minutes passed, some fluffy precipitation form. Add 1 drop 6M HOAc, some NaNO2, and add some Na3Co (NO2)6 (aq) .

Which is the soluble group of cation Group 5?

Five minutes passed, some fluffy precipitation form. Add 1 drop 6M HOAc, some NaNO2, and add some Na3Co (NO2)6 (aq) . Warm the solution for a while and cool it down. Add 1 drop 6M NH4Cl, few drops Na2HPO4. Let it react for 5 minutes. Centrifuge it.Take the precipitation.

How to treat cation Group 5 as a carcinogen?

Treat as a possible carcinogen. Divide the solution into three equal parts. Add some drops uranyl magnesium acetate in to one part of the sample which is without ammonium. Wait the reaction for 5 minutes. Five minutes passed, some fluffy precipitation form. Add 1 drop 6M HOAc, some NaNO2, and add some Na3Co (NO2)6 (aq) .