4.2.1 Chemical bonds, ionic, covalent and metallic Flashcards
What are the three types of strong chemical bonds?
Ionic bonding, Covalent bonding, Metallic bonding
What is ionic bonding?
Ionic bonding occurs between oppositely charged ions, where electrons are transferred from metal atoms to non-metal atoms.
What is covalent bonding?
Covalent bonding occurs when atoms share pairs of electrons to form strong bonds.
What is metallic bonding?
Metallic bonding occurs when atoms share delocalised electrons in a giant lattice structure.
Where do these types of bonding occur?
Ionic bonding: In compounds formed from metals and non-metals.
Covalent bonding: In most non-metallic elements and compounds of non-metals.
Metallic bonding: In metallic elements and alloys.
How are ions formed in ionic bonding?
Metal atoms lose electrons to form positively charged ions.
Non-metal atoms gain electrons to form negatively charged ions.
What electronic structure do ions have?
Ions have the electronic structure of a noble gas (Group 0).
How can ionic bonding be represented?
Using dot and cross diagrams (e.g., sodium chloride).
Visualised in 2D or 3D forms to represent ionic compounds’ structures.
What holds ionic compounds together?
Strong electrostatic forces of attraction between oppositely charged ions, acting in all directions in the lattice.
What skills are needed for ionic bonding?
Deduce if a compound is ionic from a structural diagram.
Draw dot and cross diagrams for compounds formed by metals in Groups 1 and 2 with non-metals in Groups 6 and 7.
Work out the empirical formula of an ionic compound from a given diagram.
How are covalent bonds formed?
Covalent bonds are formed when atoms share pairs of electrons.
What types of covalent substances exist?
Small molecules: e.g., water, methane, ammonia.
Polymers: Large molecules with repeating units (e.g., poly(ethene)).
Giant covalent structures: e.g., diamond, silicon dioxide.
How are covalent bonds represented?
Dot and cross diagrams for small molecules.
Lines for single bonds in molecular and giant structures.
What skills are needed for covalent bonding?
Draw dot and cross diagrams for common molecules (e.g., hydrogen, oxygen, water).
Identify substances as small molecules, polymers, or giant structures from bonding diagrams.
Recognise the limitations of different bonding models.
What is the structure of metals in metallic bonding?
Metals have a giant lattice of atoms arranged in a regular pattern.
