Question

Noble gases are a group of elements which exhibit very (a) high chemical activity (b) less diamagnetic property (c) high electronegativity (d) low chemical activity

Short answer

Noble gases exhibit (d) low chemical activity.

Step-by-step solution

Understanding Noble Gases

Noble gases are a group of elements in Group 18 of the periodic table, which includes helium, neon, argon, krypton, xenon, and radon. These gases are known for their full valence electron shell, which generally makes them chemically inert or unreactive.

Exploring the Given Options

Let's evaluate each option: (a) High chemical activity: This means the elements readily react with others, which contradicts the properties of noble gases as they are known to be very unreactive. (b) Less diamagnetic property: Diamagnetism is a weak form of magnetism that opposes applied magnetic fields, but it's not the primary characteristic of noble gases. (c) High electronegativity: Noble gases actually have low electronegativity because they generally do not attract additional electrons due to their stable electron configuration. (d) Low chemical activity: This matches the fact that noble gases are mostly inert and do not react easily with other elements.

Choosing the Correct Answer

After evaluating all possible options, we can conclude that option (d) 'low chemical activity' is the correct answer since it aligns with the known feature of noble gases being chemically inactive.

Key concepts

Periodic Table

The periodic table is an organized display of all known chemical elements. It is arranged in order of increasing atomic number, which is the number of protons in an atom's nucleus. Elements with similar chemical properties are grouped in columns, known as groups or families. One key group in the periodic table is Group 18, often referred to as the noble gases.
These include helium, neon, argon, krypton, xenon, and radon. Their unique positioning results from their full valence electron shells, which also highlight their distinct characteristics.

• Allows for easy prediction of element properties.
• Helps to understand chemical reactions and bonding.
• Aids in identifying elements with similar behavior.

Understanding the periodic table is essential for any study of chemistry, as it forms the basis for organizing information about elemental properties and trends.

Chemical Inactivity

Chemical inactivity, also known as chemical inertness, describes how unlikely an element is to participate in a chemical reaction. For noble gases, this trait is largely due to their full valence electron shell. A full outer shell means that the element has achieved a stable configuration, which naturally lessens its desire to react with other elements.

• Noble gases have a complete set of electrons in their outermost layer, typically following the octet rule.
• As a result, they exhibit minimal reactivity under normal conditions.

This characteristic is why noble gases were historically termed "inert gases." Although some compounds, like xenon hexafluoroplatinate, have been synthesized, noble gases remain largely non-reactive. This property makes them useful in applications requiring non-reactive environments, such as in light bulbs and welding.

Valence Electrons

Valence electrons are the electrons in an atom's outermost electron shell. These electrons are crucial because they determine how an element will interact with others. For most elements, having a full valence shell corresponds to increased stability and reduced reactivity.

• Noble gases naturally have full valence shells, typically numbering eight electrons, except for helium which has two.
• This full shell configuration grants them their low tendency to form chemical bonds.

Their filled valence shells mean noble gases rarely gain or lose electrons, marking them as highly stable. This results in their well-known chemical inertness and is a defining feature of their place in Group 18 of the periodic table.

Electronegativity

Electronegativity refers to an atom's ability to attract and hold onto electrons in a chemical bond. It is a fundamental concept in chemistry that helps predict bond types and chemical reactivity. Noble gases are unique in terms of electronegativity.

• They generally have low electronegativity values because their full valence electron shells make them less inclined to attract additional electrons.
• This is contrary to elements with higher electronegativity values, which actively seek to acquire electrons to achieve a stable electron configuration.

The low electronegativity contributes to noble gases' reluctance to participate in chemical bonds. While some noble gases can form compounds under specific conditions, their typical behavior is characterized by their non-reactive nature due to both their filled shells and low electronegativity.