Question

Sodium is a highly malleable substance, whereas sodium chloride is not. Explain this difference in properties.

Short answer

The difference in malleability between sodium and sodium chloride is due to their distinct atomic and molecular structures, and the way their atoms or molecules are bonded together. Sodium's metallic bonding and the presence of free-moving electrons allow the atoms to slide past each other under stress, making sodium a highly malleable substance. On the other hand, sodium chloride's ionic bonding leads to a rigid crystal lattice structure that does not allow for easy deformation. The strong electrostatic attraction between the sodium ions and chloride ions holds them firmly in place, making sodium chloride a non-malleable substance.

Step-by-step solution

Understand the concepts of malleability

Malleability is a property of materials that allows them to be hammered or rolled into thin sheets without breaking. Malleable materials can undergo deformation under stress, like pressure, due to the arrangement and bonding of their constituent atoms or molecules.

Sodium's atomic structure and bonding

Sodium (Na) is an alkali metal, which has a single electron in its outermost shell. It has a metallic bonding where the electrons in the outermost shell are free to move in a so-called "electron sea," allowing the atoms to slide past one another when stress or pressure is applied. This electron sea leads to the characteristic malleability of metals like sodium.

Sodium chloride's molecular structure and bonding

Sodium chloride (NaCl) is an ionic compound formed by the combination of sodium ions (Na+) and chloride ions (Cl-). In this compound, the positively charged sodium ions are electrostatically attracted to the negatively charged chloride ions. This strong ionic bonding leads to a crystal lattice structure, which does not allow the molecules to slide past one another easily when a force is applied to the substance.

Explaining the difference in malleability

The key difference between the malleability of sodium and sodium chloride lies in the type of bonding and their atomic/molecular structure. Sodium's metallic bonding and the presence of free-moving electrons allow the atoms to slide past each other under stress, making sodium a highly malleable substance. On the other hand, sodium chloride's ionic bonding leads to a rigid crystal lattice structure that does not allow for easy deformation. The strong electrostatic attraction between the sodium ions and chloride ions holds them firmly in place, making sodium chloride a non-malleable substance. In conclusion, the difference in malleability between sodium and sodium chloride is due to their distinct atomic and molecular structures, and the way their atoms or molecules are bonded together.