sci_phy
The Particle Model The Particle Model of Matter
Chapter summary, hard words and model exam answers for Hindi.
Free online summary and notes (Hindi). Read it here, no PDF download needed.
About the author
Physics · CBSE 10 · ICSE 10 · GCSE (AQA, Edexcel, OCR)
Summary
Solids hold shape because particles are locked in place. Gases fill any space because particles fly far apart.
These are physical changes - reversible, no new substance made. A pure substance changes at a fixed temperature.
On a heating curve this shows as flat steps. Boiling needs more energy than melting because all attractions must break.
A drop of ink spreads through still water on its own. Smoke specks jiggle because air molecules keep hitting them.
Hard words & meanings
| particle model | the idea that all matter is made of tiny particles in constant motion |
| state of matter | the physical form of a substance: solid, liquid or gas |
| change of state | a physical change between solid, liquid and gas caused by energy |
| latent heat | energy absorbed or released during a change of state with no temperature change |
| specific latent heat | energy to change the state of 1 kg of a substance, E = mL |
| density | mass per unit volume of a substance, in kg/m3 |
| diffusion | spreading of particles from high to low concentration due to random motion |
| Brownian motion | random jiggling of small particles caused by collisions with fluid molecules |
Model exam answers, grammar & audio
You have read the summary. The board-ready model answers, grammar notes, one-touch audio and writing practice for this chapter are part of Lipi©.
Unlock free with any language courseSee it, understand it, hear it read aloud, then write the exam answer with confidence, for a fraction of a tutor cost.