Question
What happens at the boiling point of a liquid?
This question was previously asked in
RRB ALP 2025 CBT 2 Mechanic Motor Vehicle Question Paper (28-Jul-2026) (Shift 1)
The correct answer is
Particles gain enough energy to change into vapour.
Boiling Point Particle Behavior
At the boiling point, a liquid undergoes a phase transition from liquid to gas (vapour). This involves significant changes in the kinetic energy and arrangement of its constituent particles.
Understanding Particle Energy at Boiling Point
- Boiling Point Definition: The temperature at which a liquid's vapor pressure equals the surrounding atmospheric pressure, allowing it to turn into a gas.
- Particle Energy: At this specific temperature, the particles (atoms or molecules) within the liquid absorb thermal energy.
- Energy Absorption: This absorbed energy increases the kinetic energy of the particles, enabling them to overcome the intermolecular forces holding them together in the liquid state.
- Phase Change: As particles gain sufficient energy, they escape from the liquid surface and bulk, transitioning into the gaseous phase (vapour). This is why bubbles form within the liquid during boiling.
Analysis of Options
- Option 1: Incorrect. Particles are always in motion, even in solids. At boiling point, their motion increases dramatically.
- Option 2: Incorrect. While particles expand, the key change is the transition to a gaseous state, not remaining liquid.
- Option 3: Incorrect. Particles gain energy and move *further apart* when changing from liquid to gas, they do not move closer together.
- Option 4: Correct. Particles gain enough kinetic energy to overcome intermolecular forces and escape the liquid phase, transforming into vapour.
Was this answer helpful?
Similar Questions
- _____ is the heat per unit mass required to change a substance from solid into liquid at the same temperature and pressure.
Important Questions from Change of state
- Latent heat is the energy required to:
The temperature at which a solid melts to become a liquid at the atmospheric pressure is called its melting point. The melting point of a solid is an indication of
The melting temperature of a solid is usually considered to be _________ the freezing point of the corresponding liquid.
At the triple point
- While ice melts at $0^\circ C$, its temperature :
Need Expert Advice?
Upcoming Exams
RRB NTPC
September 27, 2026
Test Series
Railways
RRB ALP 2026 Mock Test series
1035 Tests 1 Tests Free
809 Attempts
4.3(234)
English, Hindi
More Questions from RRB ALP
