GCSE Chemistry: Bonding, Structure, and Properties Flashcards

Vocabulary flashcards covering atomic bonding, physical properties, ionic lattices, simple and giant covalent structures, carbon allotropes, and smart materials from GCSE Chemistry revision notes.

Metals

Elements positioned on the left side of the periodic table that conduct heat and electricity, have high melting and boiling points, and are malleable, ductile, and lustrous.

Non-metals

Elements positioned on the right side of the periodic table that do not conduct electricity or heat, have low melting and boiling points, and are non-malleable, brittle, and dull.

Malleable

A property describing a material that can be hammered into sheets or hit into shape because free electrons allow metal atoms to slide over each other.

Ductile

A property describing a material that can be drawn out into wire or threads because free electrons allow metal atoms to slide over each other.

Metallic bonding

The electrostatic force of attraction between positive metal ions and a sea of free-moving (delocalised) electrons in a giant structure.

Delocalised electrons

Outer shell electrons in metals that are free to move throughout the metallic structure, allowing the metal to conduct electricity and heat.

Ionic compounds

Compounds formed by the transfer of electrons from a metal atom to a non-metal atom, creating oppositely charged ions.

Giant ionic lattice

A regular, repeating 3D arrangement of oppositely charged ions held together by strong electrostatic forces of attraction, resulting in a net overall charge of zero.

Electrical conductivity of ionic compounds

The property where ionic substances conduct electricity when in a molten liquid state or in solution because ions are free to move, but do not conduct electricity when solid.

Melting point comparison: $NaCl$ vs $MgO$

Sodium chloride has a lower melting point than magnesium oxide because $Na^+$ and $Cl^-$ ions have fewer charges than $Mg^{2+}$ and $O^{2-}$ ions, and $Na^+$ ions are larger and cannot get as close to the negative ions.

Simple molecular structures

Structures composed of a small number of atoms joined by strong covalent bonds, held together by weak intermolecular forces, giving them low melting and boiling points and no electrical conductivity.

Giant covalent structures

Strong structures containing many non-metal atoms arranged in giant lattices and joined by strong covalent bonds, resulting in very high melting points.

Diamond

A transparent, crystalline form of carbon in which each carbon atom is joined to four other carbon atoms in a giant covalent structure, making it very hard with a high melting point over $3500^\text{o}\text{C}$ and unable to conduct electricity.

Graphite

A form of carbon structured in layers where each atom is bonded to three others; delocalised fourth electrons allow it to conduct electricity, and sliding layers without covalent bonds between them make it soft and suitable as a lubricant.

Silica

A hard substance found in sand with a high melting point and a giant covalent structure similar to diamond, containing silicon and oxygen atoms instead of carbon.

Fullerenes

Molecules consisting of cages and tubes formed from different numbers of carbon atoms, used for drug delivery systems, lubricants, and catalysts.

Buckminsterfullerene

A spherical fullerene molecule composed of $60$ carbon atoms.

Nanotubes

Tube fullerenes made of rolled graphene layers with a diameter approximately $10,000$ times smaller than a human hair, possessing extreme strength, low density, and high conductivity for use in small electronic circuits.

Graphene

A single layer from a graphite structure that is the strongest material ever tested and an exceptional electrical conductor.

Smart materials

Materials with properties that react reversibly to changes in their environment, such as changes in temperature, light, or pressure.