CIE iGCSE Co-Ordinated Science C1.1 Solids, liquids and gases Exam Style Questions Paper 1
▶️ Answer/Explanation
The particle diagrams show the arrangement and spacing of particles in the three states of matter:
- Solid (Y): Particles are tightly packed in a regular, ordered arrangement (lattice). They vibrate about fixed positions but do not move around freely. The diagram labelled Y shows this regular, closely packed arrangement.
- Liquid (Z): Particles are still close together but are not in a regular arrangement. They can slide past each other and move around within the container. The diagram labelled Z shows particles close together but with a disordered arrangement.
- Gas (X): Particles are widely spaced and move rapidly in all directions. They are not held together in a fixed arrangement. The diagram labelled X shows particles far apart with no regular order.
Therefore, Y = solid, Z = liquid, and X = gas. This matches row B: Y (solid), Z (liquid), X (gas).
✅ Answer: (B)
▶️ Answer/Explanation
The separation of particles is smallest in solids and greatest in gases. When a liquid changes to a gas (evaporation/boiling), the particles gain enough energy to overcome the forces between them and move far apart, leading to the greatest increase in separation.
✅ Answer: (B)
✅ Answer: (B)
▶️ Answer/Explanation
Solid to liquid is called melting, and liquid to solid is called freezing.
Liquid to gas is called boiling or evaporating, and gas to liquid is called condensing.
Only one row in the table assigns these five terms to the correct state changes without swapping any of them.
✅ Answer: (B)
Liquid to gas is called boiling or evaporating, and gas to liquid is called condensing.
Only one row in the table assigns these five terms to the correct state changes without swapping any of them.
✅ Answer: (B)
▶️ Answer/Explanation
In process 1, cooling from 55 °C (above boiling point of 49 °C → gas state) to 45 °C (below boiling point but above melting point → liquid state) is condensation (gas → liquid).
In process 2, warming from –100 °C (below melting point of –94 °C → solid state) to –90 °C (above melting point → liquid state) is melting (solid → liquid).
✅ Answer: (D)
In process 2, warming from –100 °C (below melting point of –94 °C → solid state) to –90 °C (above melting point → liquid state) is melting (solid → liquid).
✅ Answer: (D)
▶️ Answer/Explanation
Gases are easily compressed due to widely spaced particles, while solids are not, so compressibility distinguishes them.
Solids and gases also have very different melting points, but flammability is a chemical property unrelated to physical state.
✅ Answer: (A)
Solids and gases also have very different melting points, but flammability is a chemical property unrelated to physical state.
✅ Answer: (A)