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 correct answer is (c) \\(n-1)d^{10} ns^1\\.

Step 1: Understanding Coinage Metals

Coinage metals refer to Copper (Cu), Silver (Ag), and Gold (Au). These elements have special electron configurations due to their placement in the d-block of the periodic table.

Step 2: Identify the Electron Configuration

For transition metals, particularly the coinage metals, the general electron configuration can be represented based on the d and s orbitals. As these are heavy metals, their electron configuration in the outer shell plays a crucial role.

Step 3: Analyze Given Options

Evaluate the given options to find the correct form corresponding to the known electron configuration of Cu, Ag, and Au. Generally, coinage metals in their ground state have a filled d subshell with one electron in the s subshell.

Step 4: Select the Correct Configuration

The electron configuration that describes the outer electron arrangement of the coinage metals is \((n-1)d^{10} ns^1\). This corresponds to a completely filled d orbital and a single electron in the s orbital.

Key Concepts

Coinage Metals

Coinage metals, specifically Copper (Cu), Silver (Ag), and Gold (Au), are unique elements cherished not only for their historical use in currency but also for their intriguing electron configurations. These metals are known for their excellent electrical conductivity and resistance to corrosion.
Each of these elements shares a commonality in their electron arrangements, especially in the outer shells. This distinct configuration is \((n-1)d^{10}ns^1\), which features a fully filled d subshell and a single electron in the s subshell.

• Copper (Cu): Atomic number 29, configuration ends in \([Ar] 3d^{10} 4s^1\).
• Silver (Ag): Atomic number 47, configuration concludes with \([Kr] 4d^{10} 5s^1\).
• Gold (Au): Atomic number 79, ends in \([Xe] 4f^{14} 5d^{10} 6s^1\).

This unique arrangement contributes to their lustrous appearance and high conductivity, making them invaluable not only in monetary systems but also in modern technology such as electronics and high-tech applications.

Transition Metals

Transition metals form a broad category of elements characterized by their ability to form various oxidation states and colored compounds. These metals reside in the central block of the periodic table, known as the d-block, and are marked by their partially filled d subshells.

• They include elements like Iron (Fe), Nickel (Ni), Copper (Cu), and many others.
• Their distinctive property to form different ions arises from the involvement of d electrons in bonding.
• These elements are typically hard and have high melting points, making them ideal for industrial use.

The versatility of transition metals stems from their electron configurations, generally \((n-1)d^{1-10}ns^1-2\). Such configurations allow these elements to be chemically flexible, hence their wide applications in catalysis, electronics, and metallurgy.

d-block Elements

The d-block elements, often referred to as transition elements, cover groups 3 to 12 on the periodic table. Spanning across varying properties, they form a pivotal segment due to their partially filled d orbitals.
These metals possess robust metallic characteristics and serve as the backbone of many alloying applications, and are critical for industrial chemistry.

• d-block elements include metals such as Chromium (Cr), Manganese (Mn), Copper (Cu), and more.
• They exhibit a wide range of oxidation states, making them essential as catalysts in numerous chemical reactions.
• Their electron configuration is vital to their chemical behavior, typically \((n-1)d^{1-10}ns^{0-2}\).

The combination of their chemical and physical properties underscores the significance of d-block elements in technology and industry, from forming the basis of stainless steel to enabling advancements in electronic devices.