Ncert Chapter 3 – Metals and Non-Metals

Intext Question 1. Give an example of a metal which  (i) is a liquid at room temperature. Mercury (Hg) (ii) can be easily cut with a knife. Sodium (Na) (iii) is the best conductor of heat. Silver (Ag) (iv) is a poor conductor of heat. Lead (Pb) 2. Explain the meanings of malleable and ductile. […]

corrosion resistance, thermal conductivity, malleability, and aesthetic appeal of copper make it a preferred choice for making hot water tanks compared to steel.

Aqua regia is a potent mixture of concentrated nitric acid (HNO3) and hydrochloric acid (HCl), typically in a 1:3 ratio. This mixture is one of the few solutions that can dissolve gold (Au)

Overall, the acidic nature of lemon or tamarind juice facilitates the chemical reaction with tarnish on copper vessels, making it easier to clean and restore their shine

Acidic Nature, Chemical Reaction, Solubility, Abrasive Action, Enhanced Cleaning, are effective in cleaning tarnished copper vessels

Platinum, gold and silver are highly resistant to corrosion and tarnishing, maintaining their luster and appearance over time.

Form acidic oxides. These oxides react with water to produce acidic solutions eg: carbonic acid (H2CO3), sulfurous acid (H2SO3) in water.

Coating with a protective layer such as galvanization (coating with zinc) or electroplating or Using paints

When sulfur is heated, it undergoes sublimation, turning directly from solid to gas. The gas evolved in this process is sulfur dioxide (SO2).

Anode: Impure metal M
Cathode: Pure metal M
Electrolyte: Solution containing ions of metal M in its cationic form

Amphoteric oxides are oxides that can act as both acidic and basic compounds depending on the conditions. They can react with both acids and bases to form salts and water.

Connect the battery, bulb, wires, and switch in a circuit. Touch the ends of the wires to the sample being tested. If the bulb lights up, it indicates that the sample is a conductor of electricity, suggesting it is a metal. If the bulb does not light up, it suggests that the sample is a non-metal.