Educational Communications and Technology

Educational Communications and Technology

EDD 5161A

Group 7 Chemistry

Topic: Chemical Bonding

Group Members

Chan Lam Fai Chemistry

Wong Wai Yin Chemistry

Cheung Lai Nei Chemistry

Chemical Bonding

Introduction

What will happen when two magnet put together? Why?

MAGNETIC FORCE caused 2 magnets stick together.

Bonding

ELECTROSTATIC FORCE caused 2 atoms join together.

Force between 2 atoms caused BONDING.

Types of Bonding

Ionic Bond Covalent Bond M etallic Bond

Bonding

Types of Bonding

Ionic Bond Covalent Bond M etallic Bond

Bonding

Ionic Bond

What is the chemical formula of salt? NaCl

Is NaCl neutral or a charge carrier? Neutral

Ionic Bond (Cont’d)

After dissolving in water, what would the elements become?

Ions

Are they neutral or charged? Charged

Ionic Bond (Cont’d)

Which is positive / negative charge? Sodium ion, Na+, — positive Chloride ion, Cl–, — negative

Definition of Ionic Bond

IONIC BOND is the strong non-directional electrostatic force of attraction between oppositely charge ions.

A pure ionic bond is formed by the COMPLETE transfer of one or more electrons from one atom to another.

Electron Transfer of NaCl

Na is metal or non-metal? How about Cl? Na is metal, Cl is non-metal.

Generally, electron transfers from Na (metal) to Cl (non-metal).

Why?

Electronic Configuration of Na

What is the electronic configuration of Na? (2,8,1)

Na tend to loss or gain electron to make it stable?

It tends to loss ONE electron to make it stable.

Sodium Ion

Losing one electron

Electronic Configuration of Cl

What is the electronic configuration of Cl? (2,8,7)

Cl tend to loss or gain electron to make it stable?

It tends to gain ONE electron to make it stable.

Chloride Ion

Gaining one electron

Electronic Diagram of NaCl

The electron transfer from sodium atom to chlorine atom.

It is also called an electron ‘dot/cross’ diagram (or simply electron diagram)

Simplified notation

Another Example

Let’s consider another example, magnesium fluoride.

What is the chemical formula of magnesium fluoride?

MgF2

Another Example (Cont’d)

Which one lose electron(s)? How many? Mg loses 2 electrons.

Which one gain electron(s)? How many? F gain 1 electron.

Another Example (Cont’d)

How many atoms of Mg and F involved in this electron transfer process?

1 Mg atom, 2 F atoms So, totally 3 atoms are involved in this proc

ess.

Magnesium Fluoride MgF2

What your prediction about the electronic transfer of MgF2

Homework

Draw the electronic diagram of the following compounds.– Potassium Chloride– Magnesium Chloride– Aluminum Chloride

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