Lesson 8

• states of matter
• Middelbare school
• havo, vwo
• Leerjaar 1

Period 3 

Elements

This lesson

•  Recap
• 4.3 The evolution of our understanding of the atom
• Working independently

Learning goals

• Describe the Dalton model, the Thomson model, the Rutherford model and the Bohr model
  
•  Explain how the Rutherford experiment shows that the Thomson model is not correct
•  Describe the key features of the Bohr model

What have we learned about atoms 

already?

Atoms

• Comes from the word Atomos — indivisible 
  

• The building blocks of everything in the universe
  

• There are many types of atoms called elements organised in the periodic table
  

The evolution of our understanding of the atom

Dalton — Thomson — Rutherford — Bohr 

Dalton

• All matter is made up of atoms
  
• Atoms are indivisible particles
  
• There are many types of atoms (elements)
  
• Atoms of the same elements have the same mass
  

Thomson

Plum pudding model

Thomson

Plum pudding model

• A blob of positive and negative charges
  

The Rutherford experiment

Rutherford model

Rutherford model

An atom is

• A nucleus containing protons and neutrons
  
• With a cloud of electrons around it 
  

The Bohr model

The Bohr model

• A nucleus — protons + Neutrons
  
• Electrons in fixed orbits around it
  

Working independently

Link

Working independently

Read: 4.4

Do: 4.5 exercise 1 + 2

The charge cloud model

(advanced)

The homework

Read: 4.4

Do: 4.5 exercise 1 + 2

Learning goals

• Describe the Dalton model, the Thomson model, the Rutherford model and the Both model
  
•  Explain how the Rutherford model shows that the Thomson model is not correct
•  Describe the key features of the Bohr model