What this topic covers
Topic C1: Particles has 2 subtopics:
- The particle model
- Atomic structure
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GCSE OCR Higher Combined Science Chemistry · Topic 1 of 6
Topic C1: Particles – GCSE OCR Higher Combined Science Chemistry revision notes
Choose a subtopic. Topic C1: Particles covers The particle model and Atomic structure in GCSE OCR Higher Combined Science Chemistry. 15 lessons in 2 subtopics.
Revise Topic C1: Particles for GCSE OCR Higher Combined Science Chemistry, including The particle model and Atomic structure. 15 lessons across 2 subtopics.
15
Lessons
2
Subtopics
Topic C1: Particles lessons by subtopic
15 lessons, grouped by subtopic.
The particle model
- States of Matter and Particle Theory
- Energy Changes and Forces Between Particles
- What are mixtures and their properties
- Separation techniques for mixtures
- Choosing the right separation method
- State Symbols in Chemical Equations
Atomic structure
- Early atomic models: from spheres to plum pudding
- The nuclear model: Rutherford's breakthrough
- Refining the atom: Bohr, protons and neutrons
- Electrical Charges in Atoms
- The Size and Scale of Atoms
- Mass Distribution and Atomic Particles
- Isotopes and Atomic Notation
- Understanding Relative Atomic Mass
- Electronic Structure and Energy Levels
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Frequently asked questions
What is Topic C1: Particles?
Topic C1: Particles covers The particle model and Atomic structure in GCSE OCR Higher Combined Science Chemistry. 15 lessons in 2 subtopics.
What is the plum pudding model?
The plum pudding model is Thomson's atomic model of a sphere of positive charge with negative electrons embedded throughout, like raisins in a pudding. The Early atomic models: from spheres to plum pudding notes cover this in full.
What are isotopes?
Isotopes are atoms of the same element that have the same number of protons but different numbers of neutrons. The Isotopes and Atomic Notation notes cover this in full.
How do you calculate relative atomic mass?
Relative atomic mass = sum of (isotope mass × abundance) ÷ 100. The Understanding Relative Atomic Mass notes cover this in full.
What is the formula for relative atomic mass?
The formula for relative atomic mass is Ar = sum of (isotope mass × abundance) ÷ 100. The Understanding Relative Atomic Mass notes cover this in full.
What are the changes of state?
The changes of state are melting (solid to liquid), freezing (liquid to solid), boiling (liquid to gas) and condensing (gas to liquid). The States of Matter and Particle Theory notes cover this in full.
Who discovered the neutron?
James Chadwick discovered the neutron in 1932, about 20 years after the nucleus was accepted. The Refining the atom: Bohr, protons and neutrons notes cover this in full.
What is relative atomic mass?
Relative atomic mass is the weighted mean mass of an atom of an element compared with one twelfth of the mass of a carbon-12 atom. The Understanding Relative Atomic Mass notes cover this in full.
What is the nuclear model of the atom?
The nuclear model, proposed by Rutherford in 1911, is a model of the atom where most of the mass and all the positive charge is concentrated in a tiny central nucleus, with electrons orbiting around it in mostly empty space. The The nuclear model: Rutherford's breakthrough notes cover this in full.