The changing atom L.O.: Describe how the model of the atom has changed over the years. Describe protons, neutrons and electrons in terms of relative charge.

Slides:

Advertisements

Similar presentations

08/11/2013 What level will you reach?... To get a grade D: you will label the subatomic particles in an atom and state the charge of the sub-atomic particles.

Advertisements

Elements & Atoms Atomic theory grew as a series of models that developed from experimental evidence. As more evidence was collected, the theory and models.

ATOMIC STRUCTURE. Objectives: SWBAT Identify three subatomic particles and compare their properties. Distinguish the atomic number of an element from.

Chapter 4 Atomic Structure

ATOMIC STRUCTURE AND HISTORY

Atomic Theory “History of. . . ”.

RUTHERFORD’S EXPERIMENT How he found out how atoms were put together.

The Gold Foil and the Nucleus

History of Atomic Theory

( Rutherford’s experiment ).  Before 1910, the structure of the atom was thought to correspond with the « plum pudding model ». In summary, the Plum.

History of Atomic Structure

PART ONE ATOMIC THEORY. Over the course of thousands of years our idea of what matter is made of and what the atom looks like has changed dramatically.

Science Starter: Black Boxes Groups of 2: Manipulate the box so the marble moves around the fixed object inside of the box. DO NOT OPEN THE BOX Discuss.

The Parts of an Atom.

EARLY Atomic theories.

Atomic Theory “History of... ”. The Ancient Greeks Democritus and other Ancient Greeks were the first to describe the atom around 400 B.C. The atom was.

Section 2: Atomic Discoveries

Atomic Theory. The Atom Recall the atom is the smallest particle making up an element.

27/10/2015 GCSE Radiation 27/10/2015 Structure of the atom A hundred years ago people thought that the atom looked like a “plum pudding” – a sphere of.

What is an atom??? An atom is the smallest particle of an element that retains its identity in a chemical reaction.

History of the Atom. What do you know about the atom? Put simply, the atom is the smallest particle of pure essence. For example, helium gas is made up.

STANDARD A MOST OF THE SLIDES FROM THIS POWER POINT PRESENTATION COMES FROM HOLT CHEMISTRY. PLEASE DISREGARD THE CHAPTER NUMBERS. STANDARD A ASSESSEMENT.

Chapter 4 Atomic Structure

Atomic Structure A level At The Sixth Form College Colchester.

The Structure of the Atom

26/11/2015 The Scattering experiment L/O :- To know the structure of an atom and to understand Rutherford and Marsden’s scattering experiment.

HISTORY OF THE ATOM MODERN THEORIES OF ATOMIC STRUCTURE.

Rutherford’s alpha scattering experiment. source of alpha particles thin gold foil photographic film beam of  particles most pass straight through 1 in.

Rutherford’s experiment Day 2. Last time Discussion of early atomic model- the plum pudding model To refresh your memory: – Large slightly positive mass.

Atomic Structure Mr. Rana 9/20/12. Bell Ringer Make sure you are in your assigned seat, otherwise you will be marked absent. Bell ringer is on page 13.

3-2 Radioactivity and the nucleus (10.2 pg )

Models of the Atom. Objectives Recognize that science is a progressive endeavor that reevaluates and extends what is already known. (SPI Inq.1)

The scattering experiment.  The scattering experiment.

Atomic Structure.

 Joseph John Thomson, an English scientist, provided the first hint that an atom is made of even smaller particles.  He observed that there are NEGATIVELY.

Atomic Structure Where our ideas of the atom come from and what we know now.

7: Atomic and Nuclear Physics 7.1 The Atom. Atomic Theory The Plum Pudding Model Negative charged electrons Positive charged mass.

Atomic Structure mistry/Further_Understanding_of_the_Atom.

THE STRUCTURE OF THE ATOM.  All atoms consist of 2 regions:  1) Nucleus: very small region located near the center of the atom  Proton: positively.

Ch 5: Atomic Structure. warmup All matter is composed of very small particles called atoms. In middle school science you learned about the atom. 1. Draw.

Get out your packet and open to the next notes page Write down the Essential Question: What scientists contributed to the structure of the atom?

Do Now 8/29/14  A student in the lab wanted to classify an unknown substance as an element, compound, homogeneous mixture, or heterogeneous mixture. The.

+ Evidence For The Atomic Structure Noadswood Science, 2012.

S. Aldrich HISTORY OF THE ATOM 460 BCE Democritus develops the idea of atoms He believed that you could cut objects in half, over and over again,

IP The atom and the discovery of the nucleus © Oxford University Press 2011 The atom and the discovery of the nucleus.

Atomic structure and radioactive decay

Describe the shape of an atom using your background knowledge.

Atom Definition: the smallest particle of any element that retains the properties of that element.

Atomic History and Theories

The structure of an atom…

Starter Write down the following symbol equations (balanced)

Atomic Theory “History of. . . ”.

Atomic History and Theories

ATOMIC HISTORY & ISOTOPES

Starter Activity Draw what you think an atom looks like and for extra CHALLENGE, label each part of the atom with its name and charge Current, Magnetic.

Atomic Models History of the Development of

UNDERSTANDING THE PROPERTIES OF ELEMENTS

Inside the Atom -1 Particle Mass Charge Position Proton Neutron

THE ATOMIC NUCLEUS How is the atom put together?

Atomic Theory The idea that matter is made up of atoms, the smallest pieces of matter.

P2 - Physics Radiation.

Writing an electronic structure

Development of Atomic Theory Note-taking Directions

Presentation transcript:

The changing atom L.O.: Describe how the model of the atom has changed over the years. Describe protons, neutrons and electrons in terms of relative charge and relative mass. Describe the distribution of mass and charge within an atom. Describe the contribution of protons and neutrons to the nucleus of an atom, in terms of atomic number and mass number.

Homework: Write an exam question and corresponding mark scheme Homework: Write an exam question and corresponding mark scheme. It will be used as a starter in the next lesson.

Smaller then an atom… What is a subatomic particle? Name all three Draw and label hydrogen atom Draw and label a helium atom Explain the properties of the subatomic particles Extension Draw and label a carbon atom Draw and label an alpha particle Draw and label a hydride ion (H+)

Structure of the atom A hundred years ago people thought that the atom looked like a “plum pudding” – a sphere of positive charge with negatively charged electrons spread through it… Ernest Rutherford, British scientist: I did an experiment that proved this idea was wrong. I called it the “Rutherford Scattering Experiment”

http://phet. colorado. edu/simulations/sims. php http://phet.colorado.edu/simulations/sims.php?sim=Rutherford_Scattering Ask students to come up with model (in groups)

Most particles passes straight through, but some bounced back towards the source. Come up with a model of an atom that explains this result. Remember, alpha particles are positively charged.

The Rutherford Scattering Experiment Alpha particles (positive charge) Thin gold foil Some particles passed through, some were deflected backwards Conclusion – atom is made up of a small central nucleus surrounded by electrons orbiting in shells

The structure of the atom ELECTRON – negative, mass nearly nothing PROTON – positive, same mass as neutron (“1”) NEUTRON – neutral, same mass as proton (“1”)

Task Your task is to produce a report into one of the different models of the atom to have been developed by scientists since 1890. Success criteria: Information about the key scientists who developed this model of the atom. A description of what they believed the atom looked like when they began their work. The key experiments that they did and what they found out from them. The conclusions that they drew from their work and the model of the atom that developed from their work.

Research your topic in expert groups (same numbers together, 15 min). Rearrange groups (same letter). Brief the rest of the group on your topic (15 min) Individual students to present to the class (15 min). Label students: 1a, 1b, 1c, 1d. 2a, 2b, 2c, 2d Tip: make sure you follow the success criteria.

Group 1 (Greek model):Anna, Keverne, Henry Group 2 (Thomson, plum-pudding): Sharon, Mohammed, Anthony, Esther Group 3 (Rutherford):Andreia Louise, Bilal, Christine, Christina Group 4 (Bohr and others): Buket, Kimberly, Winifred, Omolara Tina

Task: 1) Describe the differences between the “plum pudding” model and the “nuclear” model. (4 marks). 2) Use the “nuclear” model to explain the results from Rutherford’s experiment. (2 marks) 3) Why did the work of Rutherford and Marsden convince many scientists that the ‘plum pudding’ model of the atom was incorrect? (2 marks)

Task: 1) “plum pudding” vs “nuclear” model. nuclear model mass is concentrated at the centre / nucleus. (1 mark) plum pudding model mass is evenly distributed. (1 mark) nuclear model positive charge occupies only a small part of the atom. (1 mark) plum pudding model positive charge spread throughout the atom (1 mark)

Task: “plum pudding” vs “nuclear” model. nuclear model electrons orbit some distance from the centre / nucleus (1 mark) plum pudding electrons embedded in the (mass) of positive (charge) (1mark) nuclear model the atom mainly empty space (1 mark) plum pudding model is a‘solid’ mass (1 mark)

Task: 2) Use the “nuclear” model to explain the results from Rutherford’s experiment. (2 marks) nucleus must be positive to deflect/repel alpha particles ( 1 mark) nucleus (very) small so few alpha particles deflected backwards ( 1 mark)

Task: 3) Why did the work of Rutherford and Marsden convince many scientists that the ‘plum pudding’ model of the atom was incorrect? (2 marks)