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why sodium chloride has crystal lattice structure

Sodium chloride (NaCl), commonly known as table salt, has a crystal lattice structure because of the strong electrostatic forces of attraction between its positively charged sodium ions (Na+) and negatively charged chloride ions (Cl-). This type of structure is characteristic of ionic compounds.

Here's why sodium chloride has a crystal lattice structure!

  1. Ionic Bond Formation: Sodium chloride is formed by the ionic bonding between sodium (Na) and chlorine (Cl) atoms. Sodium has one valence electron and readily loses it to become a positively charged sodium ion (Na+), while chlorine readily accepts that electron to become a negatively charged chloride ion (Cl-).

  2. Formation of Ions: When sodium loses an electron, it forms a Na+ ion, which has a positive charge. When chlorine gains an electron, it forms a Cl- ion, which has a negative charge. These ions have opposite charges, and they are attracted to each other due to electrostatic forces.

  3. Arrangement in a Crystal Lattice: In a sodium chloride crystal, Na+ and Cl- ions are arranged in a three-dimensional repeating pattern, known as a crystal lattice. Each Na+ ion is surrounded by Cl- ions, and each Cl- ion is surrounded by Na+ ions. The electrostatic attraction between these ions holds them in a stable, ordered structure.

  4. High Melting and Boiling Points: The strong ionic bonds between Na+ and Cl- ions result in a high melting point and boiling point for sodium chloride. In a crystal lattice, the ions are held in fixed positions, and it takes a significant amount of energy to break these bonds and change the state of the substance from solid to liquid or gas.

  5. Brittleness: The crystal lattice structure of sodium chloride also makes it brittle. When a force is applied to a crystal of NaCl, the ions cannot easily slide past one another, and the crystal tends to shatter along planes defined by the crystal structure.

Published on: Sep 15, 2023, 12:56 AM  


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