Primary interatomic attraction responsible for the formation of solids Which fundamental interaction most directly accounts for the cohesive forces (chemical bonding) that form and hold solids together?

Introduction / Context:
Cohesion in solids arises from chemical bonding. Understanding what underlying interaction produces covalent, ionic, and metallic bonds is foundational in materials science and solid-state physics.

Given Data / Assumptions:

• Atoms contain positively charged nuclei and negatively charged electrons.
• Quantum mechanics governs allowed electronic states and Pauli exclusion.
• Macroscopic solid stability reflects many-body interatomic interactions.

Concept / Approach:
The immediate, dominant microscopic attraction binding atoms is the electrostatic (Coulomb) interaction between charges. Quantum mechanics determines how electrons occupy states and how exchange and correlation modify energy, thus setting bond types and strengths; however, these effects act on top of the Coulomb interaction rather than replacing it. Hence, the best single answer is “electrostatic interaction.”

Step-by-Step Solution:
Identify the forces: between nuclei and electrons (attractive) and electron–electron/nucleus–nucleus (repulsive).Quantum mechanics dictates orbital formation and bonding (covalent, ionic, metallic, van der Waals).Net cohesive energy emerges from Coulombic terms optimized by quantum-mechanical state occupancy.

Verification / Alternative check:
Ab initio (DFT, Hartree–Fock) calculations compute total energies from Coulomb interactions plus quantum exchange-correlation, reproducing cohesive energies and lattice constants of solids.

Why Other Options Are Wrong:
“Electromagnetic radiation pressure” is negligible for bonding. The options labeled “quantum-electrostatic” or “quantum electromagnetic” are vague and not recognized as fundamental forces distinct from Coulomb interaction. Gravity between atoms is vastly weaker than Coulomb attraction.

Common Pitfalls:

• Confusing the role of quantum mechanics (rules of occupancy) with the nature of the force (Coulomb).
• Undervaluing repulsive contributions that balance attraction to determine equilibrium spacing.

Final Answer:
Electrostatic (Coulomb) interaction between charges