Mercury & Its Compounds | Calomel & Corrosive Sublimate | NEB Class 12 Chemistry

Master Mercury (Hg) for your NEB Class 12 Chemistry Board Exams! In this video, we cover the physical and chemical properties of Mercury, plus the detailed preparation, reactions, and uses of Calomel (Hg2Cl2) and Corrosive Sublimate (HgCl2). Topics Covered: Physical Properties of Mercury (Quicksilver) Action of Acids and Air on Hg Preparation of Calomel (Mercurous Chloride) Preparation of Corrosive Sublimate (Mercuric Chloride) Test for Mercury and Nessler's Reagent Important board exam questions Topics Covered: Physical Properties of Mercury (Quicksilver) Action of Acids and Air on Hg Preparation of Calomel (Mercurous Chloride) Preparation of Corrosive Sublimate (Mercuric Chloride) Test for Mercury and Nessler's Reagent Important board exam questions for NEB Class 12. Less toxic Highly toxic (Poisonous) Reaction with $NH_3$ Turns Black Mercury (Hg) - Complete Inorganic Chemistry Guide Mercury, also known as Quicksilver (Hydrargyrum), is a d-block element in Group 12. It is the only metal that is liquid at room temperature. 1. Physical Properties Physical State: Silvery-white liquid at room temperature. Density: Very high ($13.6 \, \text{g/cm}^3$). Boiling Point: $357^\circ\text{C}$ (relatively low for a metal). Surface Tension: Extremely high; it does not "wet" glass (forms spherical droplets). Conductivity: Good conductor of electricity; fair conductor of heat. Amalgam Formation: Readily forms alloys (amalgams) with metals like $Au$, $Ag$, $Sn$, and $Zn$. Exception: It does not form an amalgam with Iron ($Fe$), which is why it is stored in iron flasks. 2. Chemical Properties Action of Air: Does not react with oxygen at room temperature. When heated to nearly its boiling point ($350^\circ\text{C}$), it forms red Mercuric Oxide Corrosive Sublimate ($HgCl_2$) Solubility Insoluble in water Soluble in water Toxicity Mercury Class 12 Chemistry, NEB Chemistry Class 12, Mercury and its compounds, Calomel preparation and properties, Corrosive sublimate Class 12, Inorganic Chemistry NEB, Class 12 Chemistry Nepal, How to prepare Calomel, Reactions of Mercury, Hg2Cl2 vs HgCl2, NEB Board Exam Chemistry, Mercury physical and chemical properties, Nessler's Reagent, Mercury compounds for boards, Class 12 Chemistry Important Questions, NEB Revision Chemistry, Chemistry