Question

why does an energy transfer not always result in phase change? write here...

Explanation:

• Energy has two roles: increasing particle kinetic energy (temperature) or overcoming intermolecular forces (phase change).
• Phase change requires energy to break/weaken intermolecular bonds (e.g., solid to liquid needs energy to overcome lattice forces).
• If energy is added below the phase - change temperature (e.g., heating water below 100°C at 1 atm), it increases molecular motion (temperature) rather than causing a phase change, as the energy is used to speed up particles (kinetic energy) instead of disrupting intermolecular forces.

Answer:

Energy transfer can increase the kinetic energy of particles (raising temperature) instead of breaking intermolecular forces (needed for phase change). Phase change occurs only at specific conditions (e.g., boiling/melting points) where energy overcomes intermolecular attractions; otherwise, energy just increases particle motion (temperature) without changing phase.