Chemical bonding - year 10 IGCSE chemistry

Ionic bonding

A chemical bond formed when one atom gives up one or more electrons to another atom between a metal and non-metal

Ion

An electrically charged atom or group of atoms that are formed by the loss or gain of electrons

Dot and cross diagram for ionic bonding

Properties of ionic compounds

1. Solid at room temperature

2. Have high melting and boiling points

3. Not an electricity conductor when solid, only in an aqueous

Covalent bonding

A chemical bond that forms when 2 non-metal atoms share a pair of electrons on the outer shells of the atoms

Dots and cross diagram for covalent bonding

Properties of covalent structures

1. Low melting and boiling points

2. Cannot conduct electricity

Giant covalent structures

Contains many atoms each joined adjacent atoms by covalent bonds and arranged into giant regular lattice

Properties of giant covalent structures

1. Very high melting points

2. Variable electrical conductivity

Allotropes

Different structural forms of the same element under the same element

Fullerene

An allotope of carbon that are connected by single and double bonds

Carbon’s allotropes

Diamond, graphene, graphite

Metallic bonding

The attraction between the positive ions and delocalized electrons that keep the ions together

Metallic lattice

Giant 3-dimensional lattice structure of positive ions (cation) surrounded by a sea of delocalized electrons

Properties of metallic bonding

1. High melting and boiling points

2. Conducts electricity

3. Malleable and ductile

Alloy

2 or more different elements mixing together 2 different metals

Cation

An ion with a positive charge

Anion

An ion with a negative charge