GCSE Physics Atoms & isotopes questions by topic

Complete the table of subatomic particles.

1. (a)Charge of the proton.[1]
2. (b)Name the neutral particle.[1]
3. (c)Charge of the electron.[1]
4. (d)Where electrons are found.[1]

An aluminium atom is written ²⁷₁₃Al.

1. (a)State the number of protons.[1]
2. (b)Calculate the number of neutrons.[1]
3. (c)State the number of electrons in the neutral atom.[1]
4. (d)State what the number 27 is called.[1]

State what an isotope is, using the terms protons and neutrons.

1. (a)Define isotope.[2]

Arrange these models in date order and name the scientist for each: nuclear atom, solid spheres, shells, plum pudding.

1. (a)First model, with scientist.[1]
2. (b)Second model, with scientist.[1]
3. (c)Third model, with scientist.[1]
4. (d)Fourth model, with scientist.[1]

This question is about the alpha-particle scattering experiment.

1. (a)Describe what the experiment involved.[2]
2. (b)State the three types of result observed.[2]
3. (c)Explain what the results proved about the structure of the atom.[2]

Atoms of element X have 19 protons and 20 neutrons; atoms of element Y have 20 protons and 20 neutrons.

1. (a)State whether X and Y are isotopes of the same element.[1]
2. (b)Give the mass number of each atom.[2]
3. (c)State the number of electrons in a neutral atom of each.[2]
4. (d)Name the element with 19 protons.[1]

Explain how an ion differs from an atom of the same element, using a sodium atom (Z = 11) forming Na⁺ as an example.

1. (a)State what changes when the ion forms.[2]
2. (b)State what stays the same.[2]
3. (c)State the charge of the Na⁺ ion in terms of elementary charges.[1]

A student says: “Rutherford’s experiment showed atoms are empty, so the plum pudding model was almost right.”

1. (a)Identify what the student gets right.[2]
2. (b)Identify what the student gets wrong, with evidence.[2]
3. (c)Write a corrected conclusion.[2]

Nuclear fission of uranium-235 (Higher).

1. (a)Describe what starts a fission event and what it produces.[3]
2. (b)Explain how a chain reaction arises.[2]
3. (c)Explain how reactors keep the chain reaction controlled.[2]

Fusion in stars (Higher).

1. (a)Describe what fuses in a star and what is formed.[2]
2. (b)Explain why stars’ cores are one of the few places fusion happens.[2]
3. (c)Explain why fusion releases energy.[2]
4. (d)State one reason controlled fusion on Earth is difficult.[1]

A radium nucleus is written ²²⁶₈₈Ra. An alpha particle is a helium nucleus, ⁴₂He.

1. (a)State the numbers of protons, neutrons and electrons in a neutral radium atom.[3]
2. (b)State the numbers of protons and neutrons in an alpha particle.[2]
3. (c)When radium emits an alpha particle, write down the mass number and atomic number of the nucleus that remains.[2]
4. (d)State which element (from Z = 86 radon, Z = 87 francium, Z = 88 radium) is formed.[1]

Explain why scientists accepted the nuclear model of the atom within a few years of the scattering experiment, while the plum pudding model had been accepted for years without such a test.

1. (a)Describe the role of the experimental evidence.[3]
2. (b)Explain why the plum pudding model survived until 1909.[1]
3. (c)State what this episode shows about how scientific knowledge develops.[2]