Loading…
Loading…
GCSE Chemistry · key term
A representation that shows every atom and every covalent bond in a molecule.
Used by AQA, Edexcel and OCR
Specification 4.7.1.1 · Paper 2
A representation that shows every atom in a molecule and every bond between the atoms.
Revise: Alkanes and Crude OilA molecular formula gives the number of each type of atom, whereas a displayed formula shows every atom and the bonds between them. In an alkane, the carbon–carbon bonds are single bonds. Each carbon forms four bonds in total and each hydrogen forms one.
Specification 1.41, 9.10C, 9.12C, 9.26C, 9.29C · Paper 1, Paper 2
A flat representation showing every atom in a molecule and the covalent bonds between them.
Revise: Limitations of ModelsA displayed formula is a two-dimensional representation: element symbols show the atoms and lines show the covalent bonds connecting them. It is quick to draw and clearly communicates which atoms are joined to which.
A representation of a molecule that shows every atom and every covalent bond.
Specification CM2.2iii, C2.2d, CM2.3i · Paper 1 (Foundation), Paper 3 (Higher)
A representation in which lines show covalent bonds between atoms.
Revise: Data TranslationConversely, a single line in a displayed formula tells you to place one shared pair between those atoms when constructing a dot-and-cross diagram. Non-bonding outer electrons may still need to be shown even though they do not become bond lines.
A two-dimensional representation showing every atom and covalent bond, with each line representing a shared pair of electrons.
A formula that uses element symbols and lines to show which atoms are joined by covalent bonds.
Paper 1 (Foundation), Paper 2 (Foundation), Paper 3 (Higher), Paper 4 (Higher)
A diagram showing every atom and every bond in a molecule, with lines representing bonds.
Revise: Bonding in simple moleculesA displayed formula helps you describe the arrangement: each letter represents an atom, and each line represents one covalent bond. It shows which atoms are joined, rather than just how many atoms are present.
A formula showing every atom and every covalent bond in a molecule, although it may not show the molecule's full three-dimensional shape.
A diagram showing every atom in a molecule and every covalent bond between the atoms.
In a displayed formula, count the atoms as well as checking that the carbon–carbon bonds are single bonds.
When asked to draw a structure, use a displayed formula: show every atom and every covalent bond. A molecular or condensed formula alone does not answer this command.
In a displayed formula, show every atom and every covalent bond; a condensed formula such as is not enough when the question asks for the structure showing all covalent bonds.
Create a free account to read GCSE Chemistry revision notes for your exam board and track your progress.