Problem 119 - A Complete Resource Book in Chemistry for JEE Main

Question

Match the following List-I List-II (a) Mercury (p) Liquid metal (b) Tungsten (q) Non-transition metal

Step-by-Step Solution

Answer

Mercury matches with Liquid metal.

Step 1: Match Mercury

Mercury is a unique element because, unlike most metals, it is a liquid at room temperature. This characteristic is unusual for metals, which are typically solid at room temperature. Therefore, the correct match for Mercury (a) is (p) Liquid metal.

Step 2: Match Tungsten

Tungsten is known for its very high melting point and density, making it a significant metal used in many applications, such as filaments in light bulbs. It is a transition metal, and since the options provided do not include transition metal, it doesn't directly match with (q) Non-transition metal.

Key Concepts

Transition Metals

Transition metals hold a special place on the periodic table. These elements are found in the middle section of the periodic table, specifically in groups 3-12. What makes them unique is their ability to form various oxidation states and complex ions. This is due to the presence of d-electrons, which can be used in bonding. Transition metals, such as iron, copper, and gold, often have vibrant colors and interesting magnetic properties.

Key characteristics of transition metals include:

• Ability to form colored compounds.
• Exhibit variable oxidation states.
• High melting and boiling points.
• Good conductors of heat and electricity.
• Often form paramagnetic compounds due to unpaired electrons.

These properties make transition metals invaluable in many industrial and chemical applications. They are critical components in the production of alloys, catalysts, and electronic devices.

Properties of Elements

Each element has a unique set of properties that define its characteristics and behavior. These properties can be chemical, such as reactivity with other elements, or physical, like melting point and density. Understanding these properties helps scientists and engineers select the right materials for various applications.

Chemical properties refer to how an element reacts with other substances. For instance, metals are typically reactive and can form compounds with nonmetals. Physical properties include aspects such as electrical conductivity, thermal conductivity, and hardness.

Some elements can have unique properties:

• Mercury, for instance, is a liquid metal at room temperature, which is rare for metallic elements.
• Tungsten boasts the highest melting point among metals, making it ideal for high-temperature applications.

Knowing these properties helps in fields like material science, chemistry, and physics to predict how elements behave under different conditions.

Metallic Elements

Metallic elements make up a significant portion of the periodic table and include both transition and post-transition metals. Metals are generally characterized by their luster, malleability, ductility, and high electrical and thermal conductivity.

Metals tend to lose electrons to form positive ions and exhibit metallic bonding characterized by an electron sea model, where electrons are free to move throughout the structure. This provides metals with their unique properties such as:

• High density and strength.
• Ability to conduct electricity and heat efficiently.
• Malleability, which allows them to be hammered or pressed into shapes without breaking.
• Ductility, meaning they can be drawn into wires.

Many metals, such as tungsten and steel, play crucial roles in construction, manufacturing, and technology, enabling advancements across various industries with their robust and versatile characteristics.