Name:____________________________ Block:_________

Types of bondingThere are three types of bond that can occur between atoms:

an occurs between a and atom (e.g. NaCl)

a occurs between atoms (e.g. I2, CH4)

a occurs between atoms in a (e.g. Cu)

Ionic bonding

Charge on the ionsMetals to form ions ( ) while non-metals electrons to form ions.( ) The number of electrons gained or lost by an atom is related to the group in which the element is found.

The elements in groups 4 and 8 (also called group 0) gain or lose electrons to form ionic compounds.

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Chemistry 11Unit 9 Chemical Bonding #2

Representing ionic bonding

Covalent bondingHow are Covalent Bonds Formed?

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Metallic bonding

Strength of metallic bonding: ion chargeThe strength of metallic bonding depends on two factors:

1.

2.

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1. The charge on the metal ionsThe on the

metal ions, the

between the ions and the electrons, and the the

metallic bonds.

A is

evidence of stronger bonds in the substance.

2. The size of the metal ionsThe the metal ion, the

closer the positive nucleus is to the delocalized

electrons.

This means there is a between the two, which creates a

metallic bond.

What are bonds?Each element is made up of just one type of atom, usually joined to other atoms of the same element by

.

Why do atoms form bonds?Bonds involve the in the outer shells of atoms.

The atoms of noble gases have outer shells and so are . This makes the noble gases very and so they do not usually form bonds.

The atoms of other elements have outer electron shells and so are . By , the atoms of these elements are able to have filled outer shells

and become stable.

What are the types of bonding? i bonding

– occurs between and atoms.

c bonding

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– occurs between atoms only.

m bonding

– occurs between metal atoms only.

All bonds involve and all bonding involve changes to the number of electrons in

the outer shells of atoms.

ASSIGNMENT #2A: answer Hebden Questions on a Separate PagePg. 172 #57

4. Complete the Following Table:

How do atoms form ions?

Atoms have an number of protons and electrons and so do not have an overall charge.

Atoms with outer electron shells are .By either or electrons, atoms can obtain full outer

electron shells and become stable.

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The of an atom shows how many electrons it must lose

or gain to have a filled outer shell.

How do atoms form positive ions?An atom that one or more electrons forms a positive ion.

, such as sodium, magnesium and iron, form positive ions.

How is a sodium ion formed?(draw the diagram below)

How do atoms form negative ions?An atom that one or more electrons forms a negative ion.

Non-metal atoms, such as chlorine, oxygen and nitrogen, form negative ions.

(draw the diagram below)

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An atom that has more protons than electrons and

so has a overall charge.

This is called a .(or cation)

An atom that has more electrons than protons and

so has a overall charge.

This is called a negative ion.(or anion)

Calculating ion charges

Electron configuration of ionsWhen gain or lose electrons to complete their outer

electron shell, they can create ions that have the .Draw the example of oxygen and fluorine:oxygen and fluorine to become negative ions

The number of and however, remain different for each element.

This means that each ion has different .What is a Polyatomic ion?

Ions can be made up of a single

atom or a .

An ion made up of a group of atoms

is called a ion.

What is ionic bonding?

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Compounds that contain ions are called . These compounds are

usually formed by a reaction between a and a .The metal and non-metal atoms have incomplete outer electron shells and so are .Electrons are from each metal atom to each non-metal atom.

The metal and the non-metal atoms form ions with outer shells and

become .The positive and negative ions are to each other.

This attraction is called ionic bonding.

How are ionic bonds formed?Sodium chloride is an ionic compound formed by the reaction between the metal sodium and the non-

metal chlorine.

The sodium ions and the chloride ions are strongly

attracted to each other.

It is this attraction that forms ionic bonds in sodium chloride and other ionic

compounds.

What is the ratio of ions? Sodium chloride (NaCl) and magnesium oxide (MgO) are ionic compounds.

In each compound, the metal needs to lose the that the

non-metal needs to gain.

Both compounds have a of

metal ions to non-metal ions, which is shown by

the formula of each compound.

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Sodium (2.8.1) needs to to form a sodium ion but oxygen (2.6) must to form an oxide ion .

sodium atoms are required for each oxygen atom and so the ratio of sodium ions to oxide

ions is .From this ratio, the formula of sodium oxide is

What is the ratio of ions needed for magnesium chloride?(draw the diagram, and indicate the ratio)

How to write the formula of an ionic compound

1.

2.

3.

4.

What is the formula of aluminium bromide? What is the formula of aluminium oxide?

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ASSIGNMENT #2B: Complete the formulae of all the possible ionic compounds from combinations of these

metals and non-metals.

Properties of Ionic CompoundsWhat is an ionic lattice?In an , when any macroscopic sample ions react together, countless

atoms will transfer electrons to form countless ions.

These oppositely charged species being produced in close proximity are drawn together into an giant, 3D,

ordered, solid, three-dimensional array of cations and anions called a . The in this structure

represents the for the ionic compound

The structure of the ionic lattice of the ionic compound.

compounds form and crystals when

Heating ionic compoundsWhy are ionic compounds solid at room temperature and have

high melting points and boiling points?

Ionic bonds are and a lot of heat is

needed to break them.

produce ionic and

so much more heat is required to break the ionic bonds in magnesium oxide than in sodium chloride.

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How can ionic compounds conduct electricity?As , ionic compounds because their ions are bonded

together in the lattice.

When (molten), the ions can break

free of the lattice and are able to move.

The and so

can carry an .

Ionic compounds are usually in water because water molecules have a slight

charge and so can the ions away from the lattice.

, the ions are free to move and can carry an electric current.

Why are ionic compounds brittle?Ionic compounds are brittle – they shatter when they are hit.

Ionic bonds are strong, so why does this happen?

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Assignment 2C: answer Hebden Questions on a Separate PagePg. 173 #58-59 61 pg 175 #62-64

WORKSHEET #1

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WORKSHEET #2

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