CHEMICAL BONDS, IONIC, COVALENT AND METALLIC
STUDENTS NEED TO RECALL: STUDENTS SHOULD BE ABLE TO:
There are three types of strong chemical bonds: ionic, covalent and metallic.
➢ explain chemical bonding in terms of electrostatic forces and the transfer or sharing of electrons.
IONIC
For ionic bonding the particles are oppositely charged ions. Ionic bonding occurs in compounds formed
from metals combined with non-metals.
When a metal atom reacts with a non-metal atom, electrons in the outer shell of the metal atom are
transferred.
Metal atoms lose electrons to become positively charged ions.
Non-metal atoms gain electrons to become negatively charged ions.
The ions produced by metals in Groups 1 and 2 and by non-metals in Groups 6 and 7 have the electronic
structure of a noble gas (Group 0).
The electron transfer during the formation of an ionic compound can be represented by a dot and cross
diagram, eg for sodium chloride.
➢ draw dot and cross diagrams for ionic compounds formed by metals in Groups 1 and 2 with non-
metals in Groups 6 and 7.
The charge on the ions produced by metals in Groups 1 and 2 and by non-metals in Groups 6 and 7 relates
to the group number of the element in the periodic table.
➢ work out the charge on the ions of metals and non-metals from the group number of the element,
limited to the metals in Groups 1 and 2, and non-metals in Groups 6 and 7.
An ionic compound is a giant structure of ions.
Ionic compounds are held together by strong electrostatic forces of attraction between oppositely charged
ions. These forces act in all directions in the lattice and this is called ionic bonding.
These compounds have high melting points and high boiling points because of the large amounts of energy
needed to break the many strong bonds.
When melted or dissolved in water, ionic compounds conduct electricity because the ions are free to move
and so charge can flow.
The structure of sodium chloride can be represented in the following forms:
Students should be familiar with the
structure of sodium chloride but do not
need to know the structures of other ionic
compounds.
➢ deduce that a compound is ionic from a diagram of its structure in one of the specified forms
➢ describe the limitations of using dot and cross, ball and stick, two and three-dimensional diagrams
to represent a giant ionic structure
➢ work out the empirical formula of an ionic compound from a given model or diagram that shows the
ions in the structure.
STUDENTS NEED TO RECALL: STUDENTS SHOULD BE ABLE TO:
There are three types of strong chemical bonds: ionic, covalent and metallic.
➢ explain chemical bonding in terms of electrostatic forces and the transfer or sharing of electrons.
IONIC
For ionic bonding the particles are oppositely charged ions. Ionic bonding occurs in compounds formed
from metals combined with non-metals.
When a metal atom reacts with a non-metal atom, electrons in the outer shell of the metal atom are
transferred.
Metal atoms lose electrons to become positively charged ions.
Non-metal atoms gain electrons to become negatively charged ions.
The ions produced by metals in Groups 1 and 2 and by non-metals in Groups 6 and 7 have the electronic
structure of a noble gas (Group 0).
The electron transfer during the formation of an ionic compound can be represented by a dot and cross
diagram, eg for sodium chloride.
➢ draw dot and cross diagrams for ionic compounds formed by metals in Groups 1 and 2 with non-
metals in Groups 6 and 7.
The charge on the ions produced by metals in Groups 1 and 2 and by non-metals in Groups 6 and 7 relates
to the group number of the element in the periodic table.
➢ work out the charge on the ions of metals and non-metals from the group number of the element,
limited to the metals in Groups 1 and 2, and non-metals in Groups 6 and 7.
An ionic compound is a giant structure of ions.
Ionic compounds are held together by strong electrostatic forces of attraction between oppositely charged
ions. These forces act in all directions in the lattice and this is called ionic bonding.
These compounds have high melting points and high boiling points because of the large amounts of energy
needed to break the many strong bonds.
When melted or dissolved in water, ionic compounds conduct electricity because the ions are free to move
and so charge can flow.
The structure of sodium chloride can be represented in the following forms:
Students should be familiar with the
structure of sodium chloride but do not
need to know the structures of other ionic
compounds.
➢ deduce that a compound is ionic from a diagram of its structure in one of the specified forms
➢ describe the limitations of using dot and cross, ball and stick, two and three-dimensional diagrams
to represent a giant ionic structure
➢ work out the empirical formula of an ionic compound from a given model or diagram that shows the
ions in the structure.
