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EnglandCombined Science

Chemistry: Particles

6 dot points across 6 inquiry questions. Click any dot point for a focused answer with worked past exam questions where available.

What is an atom made of, and how do we describe atoms using atomic number and mass number?

The structure of the atom (protons, neutrons and electrons), relative charges and masses, atomic number and mass number, isotopes, electronic structure, and the development of the model of the atom from Dalton to the nuclear model.
A focused answer to the OCR Gateway GCSE Combined Science A topic C1 on atomic structure, covering protons, neutrons and electrons, relative charges and masses, atomic number and mass number, isotopes, electronic structure, and the development of the atomic model.
9 min answer →

How do atoms join together by ionic, covalent and metallic bonding to make compounds?

Ionic bonding and the formation of ions, covalent bonding and shared electron pairs, metallic bonding and the sea of delocalised electrons, dot and cross diagrams, and how the type of bonding is decided by the elements involved.
A focused answer to the OCR Gateway GCSE Combined Science A topic C2 on bonding, covering ionic bonding and the formation of ions, covalent bonding with shared electron pairs, metallic bonding with delocalised electrons, dot and cross diagrams, and how bonding type is decided.
9 min answer →

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

The particle model of solids, liquids and gases, the arrangement and movement of particles in each state, changes of state and their names, the energy changes involved, and the limitations of the simple particle model.
A focused answer to the OCR Gateway GCSE Combined Science A topic C1 on the particle model, covering the arrangement and movement of particles in solids, liquids and gases, the changes of state and their names, the energy changes, and the limitations of the simple particle model.
9 min answer →

How does the structure and bonding of a substance explain its properties?

The properties of ionic compounds, simple molecular substances, giant covalent structures (diamond, graphite, graphene) and metals, related to their structure and bonding, and the properties of nanoparticles and polymers.
A focused answer to the OCR Gateway GCSE Combined Science A topic C2 on properties of materials, covering ionic compounds, simple molecules, giant covalent structures such as diamond and graphite, metals and alloys, and nanoparticles and polymers, all linked to structure and bonding.
9 min answer →

What is the difference between an element, a compound and a mixture, and how are mixtures separated?

Elements, compounds and mixtures, the difference between mixtures and compounds, purity and formulations, and the separation techniques of filtration, crystallisation, simple and fractional distillation and chromatography.
A focused answer to the OCR Gateway GCSE Combined Science A topic C2 on elements, compounds and mixtures, covering the difference between mixtures and compounds, purity and formulations, and the separation techniques of filtration, crystallisation, distillation and chromatography.
9 min answer →

How is the periodic table organised, and how do the properties of the groups change?

The arrangement of the periodic table by atomic number into groups and periods, the development by Mendeleev, the link between group number and outer electrons, and the properties and trends of Group 1, Group 7 and Group 0 elements.
A focused answer to the OCR Gateway GCSE Combined Science A work on the periodic table, covering the arrangement by atomic number into groups and periods, Mendeleev's development, the link between group and outer electrons, and the trends in Group 1, Group 7 and Group 0.
9 min answer →