GROUP 1 EXPERIMENTAL NOTES FROM MAAM

Question 1

They separate from other cations when precipitated with dilute hydrochloric acid

Answer 1

Group 1 Cations

Question 2

The color of group 1 cations’ precipitate

Answer 2

White precipitate

Question 3

It easily become soluble when dissolved in hot water, thus heating the solution will allow it to be dissolved back in water

Answer 3

Lead Chloride

Question 4

Precipitating agent for Lead (II) ion

Answer 4

Potassium Chromate

Question 5

A. Chemical Reaction when Lead (II) ion is exposed with Potassium Chromate.
B. The color of precipitate

Answer 5

Pb^2+ + CrO4^-2 —> PbCrO4
Yellow Precipitate

Question 6

A. Separating agent for silver and mercurous ion
B. Color of the precipitate of mercury

Answer 6

Dilute ammonia; black precipitate

Question 7

Chemical reaction of separating silver and mercurous ion with dilute ammonia

Answer 7

AgCl + NH3 <—-> Ag(NH3)3+ + Cl

Question 8

A. Precipitating agent to confirm Silver Ion

B. Chemical Reaction

Answer 8

Nitric Acid

Ag(NH3)3+ + Cl- + H3O+ <—–> AgCl (white precipitate) + H2O + NH4+

Question 9

How to confirm for Mercurous ion

Answer 9

Acidify first HgNH2Cl
Precipitating agent: Stannous chloride
Chemical Reaction: HgCl2+ SnCl2 ↔ Hg2Cl2 (white precipitate) + SnCl2 ↔ Hg (black precipitate) + SnCl6-