Problem 47 - A Complete Resource Book in Chemistry for JEE Main

Question

What is the general outer configuration of the coinage metals? (a) \(\mathrm{ns}^{2} \mathrm{np}^{6}\) (b) \((\mathrm{n}-1) \mathrm{d}^{9} \mathrm{~ns}^{2}\) (c) \((\mathrm{n}-1) \mathrm{d}^{10} \mathrm{~ns}^{1}\) (d) \((\mathrm{n}-1) \mathrm{d}^{10} \mathrm{~ns}^{2}\)

Step-by-Step Solution

Answer

The general outer configuration for coinage metals is \\( (n-1) d^{10} ns^{1} \\. Option (c).

Step 1: Understanding Coinage Metals

Coinage metals refer to copper (Cu), silver (Ag), and gold (Au). These elements are known for their characteristic outer electron configuration.

Step 2: Identify Typical Electron Configuration

The typical outer electron configuration for the coinage metals includes a filled \( (n-1) \)d subshell and a single electron in the s subshell.

Step 3: Determine the Correct Configuration

Given the choices, \( \text{option (c):} \ (n-1) d^{10} ns^{1} \) represents the configuration where the d subshell is completely filled, and there is one electron in the s subshell, which is characteristic of coinage metals.

Key Concepts

Coinage Metals

Coinage metals belong to a special group of elements, consisting of copper (Cu), silver (Ag), and gold (Au). These elements have historically been used to make coins because they are relatively non-reactive and possess an innate capability to resist oxidation and corrosion, a property that preserves their appearance over long periods. This stability makes them ideal for long-lasting and durable currency.

These metals are known for their excellent electrical and thermal conductivity, making them popular choices in electrical components and thermal applications. The allure of coinage metals also lies in their attractive and lustrous appearance, plus their ability to be easily shaped, offering both aesthetic and functional advantages.

Copper Silver Gold

Copper, silver, and gold, have been treasured by civilizations for centuries. Their properties make them useful for a variety of applications:

• Copper: Copper is known for its reddish-brown color and is commonly used in electrical wires due to its exceptional conductivity. It also features in plumbing and roofing because of its durability.
• Silver: Silver has the best electrical conductivity of all metals and is used extensively in electronics, jewelry, and cutlery. Its vibrant sheen makes it a favorite in decorative items.
  
  
• Gold: Gold is renowned for its rich yellow color and unparalleled resistance to corrosion. Its ductility and malleability allow it to be shaped into fine jewelry and coins. Due to its non-reactive nature, it has significant value in electronics as well.

These properties make copper, silver, and gold indispensable in various industries, from technology to fashion. Their natural beauty and practicality ensure they remain integral in both ancient and modern uses.

Electron Configuration Concepts

Electron configuration is a key concept in chemistry that describes the distribution of electrons in an atom or molecule. Understanding the electron configuration helps predict an element's chemical behavior and properties.

In the case of the coinage metals, the electron configuration plays a critical role because it directly influences their stability and conductivity. Coinage metals feature a distinct outer electron configuration pattern:

• They possess a filled \( (n-1) d^{10} \) subshell, ensuring that the d orbitals are fully populated, enhancing their chemical stability.
• There is a single electron in the \( ns^1 \) subshell, which is responsible for their conductivity.
  
  

This configuration is unique among elements and contributes to the excellent conductive properties of these metals. It is this configuration, \( (n-1) d^{10} ns^{1} \), that defines their status as coinage metals, enabling their widespread use in monetary and decorative applications.