Giant Ionic and Covalent Structures

• Chem
• Secondary Education

• You can go to the bathroom before the start. Leaving the room during our session is NOT allowed.
• Keep your shirt tucked in. 
• Prepare your learner's book and notebook.
• Put your phone in the tray.

Before we begin:

• build the giant structures of salt, diamond and graphite
• present the model to the class

Lesson Goals

• What conclusion can you make for this diagram?

• "Opposite attracts."
• In an ionic lattice structure, "electrostatic force of attraction" keeps the particles together.

MAIN IDEA

• What is the difference between the structure of diamond and the structure of graphite?

Enquiry Question

• each carbon atom bonds with four other carbons, forming a tetrahedron

Diamond

• All the covalent bonds are identical, very strong.
• There are NO intermolecular forces.

Diamond

Physical properties:

- does NOT conduct electricity

- very high melting point extremely dense and hard

Diamond

• Each carbon atom is bonded to three others forming layers of hexagonal-shaped forms, leaving one free electron per carbon atom

Graphite

• Free (delocalised) electrons exist in between the layers and are free to move through the structure and carry charge, hence graphite CAN conduct electricity.

Graphite

• The covalent bonds within the layers are very strong BUT the layers are connected to each other by weak forces only, hence the layers CAN slide over each other making graphite slippery and smooth

Graphite

PHYSICAL PROPERTIES

- CAN conduct electricity

- has VERY HIGH melting point

- is soft and slippery, less dense than diamond

Graphite

3D Model-making

• Group work
• Make 3D model of:

- T1: Ionic

- T 2, 5: Diamond

- T3, 4: Graphite 

• You only have 10 minutes.
• Checking!

Presentation

• Tuesday - Properties of Ionic and covalent substances
• Wednesday - Scientific investigation
• Thursday - End of Unit 2 Test 

Up next!

Self - Evaluation
😁 - I can do this! I am ready to try something new.
😅 - I am getting there! I need a bit of help. I am a bit unsure. I might need to practice.
😬 - I need help! I don't understand this. I am not ready to move on yet.

😁

😅

😬