Question

The cations and anions are arranged in alternate form in:

• A. Metallic crystal
• B. Ionic crystal
• C. Co - valent crystal
• D. Semi - conductor crystal

Answer 1

The Correct Option is B

The question asks which type of crystal structure consists of cations and anions arranged alternately. The correct option is an ionic crystal. Let's explore why this is the case and rule out the other options:

1. Ionic Crystal:
   • Ionic crystals are made up of positive ions (cations) and negative ions (anions) held together by strong electrostatic forces of attraction.
   • These oppositely charged ions are arranged in a regular, repeating pattern to minimize repulsion and maximize attraction, which often results in alternating cation and anion arrangement.
   • A common example of an ionic crystal is sodium chloride (NaCl), where Na⁺ and Cl^- ions alternate in a regular array.
2. Metallic Crystal:
   • Metallic crystals are composed of metal cations surrounded by a 'sea' of delocalized electrons.
   • They do not have an alternating pattern of cations and anions since they primarily consist of metal atoms.
3. Covalent Crystal:
   • Covalent crystals consist of atoms connected by covalent bonds in a continuous network.
   • Materials like diamond and silicon carbide do not have an ionic arrangement of oppositely charged ions.
4. Semi-conductor Crystal:
   • Semi-conductors are usually covalent in nature, such as silicon and germanium, where atoms are connected through covalent bonds.
   • They do not exhibit alternating cation and anion structures like ionic crystals.

Therefore, the arrangement of cations and anions in an alternate pattern is a characteristic property of ionic crystals, making it the correct answer.