Question

Which of the following statements is wrong? (1) The nature of bonding in diamond is only covalent while in graphite both covalent and Van der Waal's forces cxist. (2) Diamond and graphitc are allotropes of carbon. (3) Diamond is a thermodynamically stable allotrope while graphite is thermodynamically unstable allotrope. (4) Diamond is chemically inert while graphite is chemically reactive allotropes.

Short answer

Statement 3 is wrong.

Step-by-step solution

Understanding the Question

Identify the statements given about the nature of diamond and graphite and determine which one is incorrect.

Analyzing Statement 1

Statement 1: The nature of bonding in diamond is only covalent while in graphite both covalent and Van der Waals forces exist. This is correct. Diamond has a three-dimensional covalent bond network, and graphite has layers of carbon atoms bonded covalently within layers and weak Van der Waals forces between layers.

Analyzing Statement 2

Statement 2: Diamond and graphite are allotropes of carbon. This is correct. Allotropes are different forms of the same element; diamond and graphite are both forms of carbon.

Analyzing Statement 3

Statement 3: Diamond is a thermodynamically stable allotrope while graphite is thermodynamically unstable. This is incorrect. Graphite is the thermodynamically stable form of carbon at standard temperature and pressure, not diamond.

Analyzing Statement 4

Statement 4: Diamond is chemically inert while graphite is chemically reactive. This is correct. Diamond is chemically inert due to its strong covalent bonds, while graphite's layered structure makes it more reactive.

Key concepts

diamond and graphite properties

Diamonds and graphite might look different, but they are both made from carbon atoms. They are known as allotropes of carbon.
The main difference lies in their structures and properties.

• Diamond: Diamonds are incredibly hard. This is because each carbon atom is bonded to four other carbon atoms in a strong covalent bond, creating a three-dimensional lattice. This hardness makes diamonds ideal for cutting tools and jewelry.
• Graphite: Graphite, on the other hand, is soft and slippery. It is made up of layers of carbon atoms bonded in hexagonal patterns. These layers are held together by weak Van der Waals forces. This means the layers can slide over each other easily, which is why graphite is used in pencils and as a lubricant.

Despite their differences in properties and uses, both diamond and graphite are purely made of carbon.

nature of chemical bonding

Chemical bonding is what holds the atoms together in different substances.
Let's take a closer look at how bonding differs in diamond and graphite.

• In diamond, each carbon atom is bonded covalently to four other carbon atoms. These covalent bonds create a strong, rigid, three-dimensional structure. This makes diamonds extremely hard.
• In graphite, carbon atoms are bonded covalently in layers, but the layers themselves are held together by much weaker Van der Waals forces. This gives graphite its unique properties like being slippery to touch and making it a good conductor of electricity within the layers.

Understanding these bonds helps explain why diamond is hard and transparent, while graphite is soft and opaque.

thermodynamic stability

Thermodynamics is the study of heat and energy. When we talk about the thermodynamic stability of diamond and graphite, we refer to how stable these substances are under standard conditions.

• Diamond: Even though diamonds are very hard and durable, they are not the most thermodynamically stable form of carbon.
• Graphite: In contrast, graphite is actually more stable thermodynamically. This means that at standard temperature and pressure, graphite is more common and stable than diamond.

This difference is crucial for understanding natural processes and industrial applications. For example, over millions of years, carbon can transform into diamond naturally under extreme heat and pressure, but these conditions are not stable. In everyday conditions, carbon prefers the structure of graphite, making it more abundant and stable.