CIE iGCSE Co-Ordinated Science P2.1.1 States of matter Exam Style Questions Paper 4
Question
- peak X is positive and peak Y is negative
- peak Y has a larger magnitude than peak X
On Fig. 9.2, sketch the data which would be obtained if a coil containing 400 turns was used with the same magnet.
Place ticks in Table 9.1 against each statement that is correct for potential difference and for electromotive force (e.m.f.).
You may place one or two ticks in each row. The first row has been done for you.
In a solid, the arrangement of atoms is ……………………… .
The forces between atoms are ……………………… which allows the atoms to ……………………… but keeps them in a ……………………… position.
Describe how thermal energy is transferred in copper.
Most-appropriate topic codes (Cambridge IGCSE Co-ordinated Sciences 0654):
• Topic P4.5.1 — Electromagnetic induction (Part (a))
• Topic P4.2.3 — Voltage (electromotive force and potential difference) (Part (b))
• Topic P2.1.1 — States of matter (Part (c))
• Topic P2.3.1 — Conduction (Part (d))
▶️ Answer/Explanation
(a)(i) The S pole causes peak X; the N pole causes peak Y; the magnet’s speed increases as it falls
As the magnet falls, its south pole passes through the coil first, inducing the positive peak X.
Its north pole passes through next, inducing the negative peak Y.
Peak Y is larger because the magnet has accelerated under gravity and is moving faster by the time its north pole passes through, inducing a greater e.m.f.
(a)(ii) Same shape graph, crossing the x-axis at the same point, but with both peaks lower
Halving the number of turns halves the induced e.m.f. at every point, since e.m.f. is proportional to the number of turns.
The overall shape and timing of the graph remain unchanged since the magnet’s motion is unaffected.
(b)
E.m.f. relates to the energy supplied by the source, while potential difference relates to the energy transferred by a circuit component.
Both are equal to work done per unit charge and are measured in volts.
(c) Regular/ordered (a lattice); strong forces; vibrate; fixed position
In a solid, atoms are arranged in a regular, ordered lattice.
Strong forces of attraction hold the atoms close together, allowing them only to vibrate about fixed positions rather than move freely.
(d) Atoms vibrate; vibrations pass to neighbouring atoms; free electrons also transfer energy
Atoms in copper vibrate more vigorously when heated.
These vibrations are passed on from atom to atom through the lattice.
Copper’s free (delocalised) electrons also move and transfer thermal energy quickly through the metal.
Question
Complete Fig. 12.1 to show the paths taken by alpha particles and gamma rays as they pass through an electric field.
Use the correct nuclide notation to complete the decay equation for carbon-14.
The temperature of the nitrogen is increased.
Explain the effect that increasing the temperature of the gas has on the pressure in the gas.
Use ideas about molecules in your answer.
Most-appropriate topic codes (Cambridge IGCSE Co-ordinated Sciences 0654):
• Topic P5.2.2 — The three types of nuclear emission (Parts (a)–(b))
• Topic P2.1.1 — States of matter (Part (c))
▶️ Answer/Explanation
(a)(i) Alpha: He nucleus, low penetrating ability; Gamma: high penetrating ability
An alpha particle is a helium nucleus (2 protons and 2 neutrons) with low penetrating ability.
Gamma radiation, being electromagnetic radiation with low ionising effect, has high penetrating ability.
(a)(ii) Alpha curves towards negative plate; gamma travels straight
Alpha particles are positively charged, so they curve towards the negative plate in the electric field.
Gamma rays have no charge, so they pass straight through the electric field without deviating.
(b) \(^{14}_{6}\text{C} \rightarrow \, ^{14}_{7}\text{N} + \, ^{0}_{-1}\beta\)
In beta decay, the nucleon (mass) number stays the same (14).
The proton (atomic) number increases by 1 (from 6 to 7) as a neutron converts to a proton, emitting a beta particle of charge −1 and negligible mass.
(c)(i) Particles far apart in a gas, touching in a solid
In a gas, the particles are far apart with large spaces between them, so they can be pushed closer together (compressed).
In a solid, the particles are already touching, so there is no space for them to be pushed closer together.
(c)(ii) Water cannot be compressed
In a liquid such as water, the molecules are touching, with little or no space between them.
Since there are no significant gaps to reduce, water cannot be compressed.
(c)(iii) Increasing temperature increases pressure
As temperature increases, the kinetic energy/speed of the gas molecules increases.
The molecules collide with the walls of the container more often and with greater force.
This increases the force per unit area on the walls, so the pressure increases.