S1 Science: States Of Matter And The Particle Model (Paper 3 (challenge))

S1 Science: States of Matter and the Particle Model (Paper 3 (challenge))

2026-11-14

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Tutor Prep Guide · The three states, particle arrangement and motion, changes of state and latent heat

S1 Science: States of Matter and the Particle Model (Paper 3 (challenge))

This paper raises the level: density and floating, latent heat of fusion and vaporisation, pressure changes in a sealed container, and exceptions such as sublimation.

Direct answers　Write the formula before substituting: energy is mass times latent heat and density is mass over volume, and carry the units through. The word always is the trap: not every heated solid melts first, because dry ice sublimes straight to a gas.

01　Paper details (check answers afterwards)

Item	Detail
Questions	10
Suggested time	20
Difficulty mix	Intermediate 3 · Foundation 3 · Challenge 3 · Error redo 1
Chapter	Chapter: S1 Science: States of Matter and the Particle Model
Level	S1

02　Questions (10 items)

IntermediateInk spreads through water. Which property of particles does this show?
FoundationWhy can liquids and gases flow but solids cannot?
IntermediateWater has a density of 1.00 g/cm³. What is the density of ice and why does it float?
ChallengeHow much energy is needed to melt 20 g of ice completely? (latent heat of fusion 334 J/g)
IntermediateSteam at 100 °C burns worse than water at 100 °C. Why?
FoundationThe temperature rises from 30 °C to 45 °C. By how many degrees?
ChallengeA gas is heated in a sealed rigid container. What happens?
FoundationWater left in a room for a few days becomes less. Is this evaporation or boiling?
Error redoA student says the particles disappear when ice melts. What is wrong?
ChallengeA student says every solid melts into a liquid when heated. What is wrong?

03　Answers and one-line notes

#	Answer	One-line note
1	Particles move randomly all the time	Particle motion spreads the ink through the whole beaker until the colour is even.
2	Particles in liquids and gases can slide past each other, while particles in a solid only vibrate in fixed positions	Flowing needs particles to change position, and the close packing of a solid prevents that.
3	About 0.92 g/cm³, which is less than water, so it floats	Ice particles form a more open structure that takes up more volume, so ice is less dense than water.
4	6 680 J	20 times 334 is 6 680, so 6 680 J of energy is needed.
5	Condensing steam also releases latent heat	Besides cooling down, the steam condenses on the skin and releases a large amount of latent heat.
6	15 °C	45 minus 30 is 15, so the temperature rose by 15 °C.
7	The pressure of the gas rises	Faster particles hit the walls more often and harder, so the pressure goes up.
8	Evaporation	Room temperature is far below 100 °C, so only surface particles escape into the air.
9	The number of particles stays the same, only their arrangement changes	A change of state neither creates nor destroys particles; they simply stop being fixed in place.
10	Some solids turn straight into a gas, which is called sublimation	Dry ice, for example, becomes carbon dioxide gas at room temperature without becoming a liquid first.

04　What to do after marking

After marking, redo only the wrong items and write down which step went wrong (formula, unit, or misread number).
Repeat the same item two days later; move to the next paper only when both attempts are correct.
Parents only need the answer and note columns; there is no need to explain every item.

For particle model questions ask three things: which state the substance is in, how closely the particles are packed, and how their motion changes on heating or cooling.Tutor Registration →

Questions and answers are written originally by the TutorZone team and are not taken from any school, publisher or examination authority paper. Every value is checked by computer.