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C1 Particles

5 dot points across 5 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

What is inside an atom, and what do the atomic number and mass number tell us?

The sub-atomic particles and their relative masses and charges, the nucleus and electrons, atomic number and mass number, isotopes, relative atomic mass, and the size and scale of atoms.
A focused answer to OCR Gateway GCSE Chemistry A topic C1.2, covering protons, neutrons and electrons and their relative masses and charges, atomic number and mass number, isotopes, calculating relative atomic mass, and the size and structure of the atom.
9 min answer →

How did the model of the atom change as new experimental evidence was gathered?

The historical development of the atomic model from Dalton to the nuclear model, including the plum pudding model, the alpha particle scattering experiment, the discovery of the nucleus, Bohr's shells, and the discovery of the neutron.
A focused answer to OCR Gateway GCSE Chemistry A topic C1.2 on how the atomic model developed, covering Dalton, the plum pudding model, the alpha particle scattering experiment and the nuclear model, Bohr's energy levels, and the discovery of protons and neutrons.
8 min answer →

How are electrons arranged in atoms, and how does this link to the periodic table?

The arrangement of electrons in shells (energy levels), writing electronic configurations for the first 20 elements, and the link between the number of outer-shell electrons and an element's group and chemical behaviour.
A focused answer to OCR Gateway GCSE Chemistry A topic C1.3, covering how electrons fill shells (energy levels), writing electronic configurations for the first 20 elements, and how the number of outer electrons determines an element's group and reactivity.
8 min answer →

How does the particle model explain the three states of matter and changes of state?

The particle model, the three states of matter, changes of state, the energy and arrangement of particles in solids, liquids and gases, and the limitations of the simple model.
A focused answer to OCR Gateway GCSE Chemistry A topic C1.1, covering the particle model, the arrangement and energy of particles in solids, liquids and gases, changes of state, heating and cooling curves, and the limitations of the simple particle model.
9 min answer →

How is the periodic table organised, and how do the properties of Group 1, Group 7 and Group 0 change down the group?

The structure of the periodic table, the work of Mendeleev, metals and non-metals, and the trends in reactivity and properties of Group 1 (alkali metals), Group 7 (halogens) and Group 0 (noble gases).
A focused answer to OCR Gateway GCSE Chemistry A topic C1.3 on the periodic table, covering Mendeleev's contribution, the arrangement by atomic number, metals and non-metals, and the trends in Group 1 alkali metals, Group 7 halogens and Group 0 noble gases.
9 min answer →