460 BC - Greek philosopher proposes the existence of the atom
He pounded materials until he made them into smaller and smaller parts
He called them atoma which is Greek for “indivisible”.
Atomic Structure and the Periodic TablePaul Schumann
Sharon Williams, Water Valley High School
Presented at CAST 2008, ACT2 Strand, 11/6/09
Objectives
Identify important developments in the history of atomic theory.
Summarize Dalton’s atomic theory.
Describe the size of an atom.
Distinguish among protons, electrons, and neutrons in terms of relative mass and change.
Describe the structure of an atom, including the location of the protons, electrons, and neutrons with respect to the nucleus.
Explain how the atomic number identifies an element.
Use the atomic number and mass number of an element to find the number of protons, electrons, and neutrons.
Explain how isotopes differ and why the atomic masses of elements are not whole numbers.
Calculate the average atomic mass of an element from isotope data.
Quantum mechanical model of atom belongs to XI standard Chemistry which describes the quantum mechanics concept of atom, quantum numbers, shape and energies of atomic orbitals.
460 BC - Greek philosopher proposes the existence of the atom
He pounded materials until he made them into smaller and smaller parts
He called them atoma which is Greek for “indivisible”.
Atomic Structure and the Periodic TablePaul Schumann
Sharon Williams, Water Valley High School
Presented at CAST 2008, ACT2 Strand, 11/6/09
Objectives
Identify important developments in the history of atomic theory.
Summarize Dalton’s atomic theory.
Describe the size of an atom.
Distinguish among protons, electrons, and neutrons in terms of relative mass and change.
Describe the structure of an atom, including the location of the protons, electrons, and neutrons with respect to the nucleus.
Explain how the atomic number identifies an element.
Use the atomic number and mass number of an element to find the number of protons, electrons, and neutrons.
Explain how isotopes differ and why the atomic masses of elements are not whole numbers.
Calculate the average atomic mass of an element from isotope data.
Quantum mechanical model of atom belongs to XI standard Chemistry which describes the quantum mechanics concept of atom, quantum numbers, shape and energies of atomic orbitals.
Macroeconomics- Movie Location
This will be used as part of your Personal Professional Portfolio once graded.
Objective:
Prepare a presentation or a paper using research, basic comparative analysis, data organization and application of economic information. You will make an informed assessment of an economic climate outside of the United States to accomplish an entertainment industry objective.
A Strategic Approach: GenAI in EducationPeter Windle
Artificial Intelligence (AI) technologies such as Generative AI, Image Generators and Large Language Models have had a dramatic impact on teaching, learning and assessment over the past 18 months. The most immediate threat AI posed was to Academic Integrity with Higher Education Institutes (HEIs) focusing their efforts on combating the use of GenAI in assessment. Guidelines were developed for staff and students, policies put in place too. Innovative educators have forged paths in the use of Generative AI for teaching, learning and assessments leading to pockets of transformation springing up across HEIs, often with little or no top-down guidance, support or direction.
This Gasta posits a strategic approach to integrating AI into HEIs to prepare staff, students and the curriculum for an evolving world and workplace. We will highlight the advantages of working with these technologies beyond the realm of teaching, learning and assessment by considering prompt engineering skills, industry impact, curriculum changes, and the need for staff upskilling. In contrast, not engaging strategically with Generative AI poses risks, including falling behind peers, missed opportunities and failing to ensure our graduates remain employable. The rapid evolution of AI technologies necessitates a proactive and strategic approach if we are to remain relevant.
The Roman Empire A Historical Colossus.pdfkaushalkr1407
The Roman Empire, a vast and enduring power, stands as one of history's most remarkable civilizations, leaving an indelible imprint on the world. It emerged from the Roman Republic, transitioning into an imperial powerhouse under the leadership of Augustus Caesar in 27 BCE. This transformation marked the beginning of an era defined by unprecedented territorial expansion, architectural marvels, and profound cultural influence.
The empire's roots lie in the city of Rome, founded, according to legend, by Romulus in 753 BCE. Over centuries, Rome evolved from a small settlement to a formidable republic, characterized by a complex political system with elected officials and checks on power. However, internal strife, class conflicts, and military ambitions paved the way for the end of the Republic. Julius Caesar’s dictatorship and subsequent assassination in 44 BCE created a power vacuum, leading to a civil war. Octavian, later Augustus, emerged victorious, heralding the Roman Empire’s birth.
Under Augustus, the empire experienced the Pax Romana, a 200-year period of relative peace and stability. Augustus reformed the military, established efficient administrative systems, and initiated grand construction projects. The empire's borders expanded, encompassing territories from Britain to Egypt and from Spain to the Euphrates. Roman legions, renowned for their discipline and engineering prowess, secured and maintained these vast territories, building roads, fortifications, and cities that facilitated control and integration.
The Roman Empire’s society was hierarchical, with a rigid class system. At the top were the patricians, wealthy elites who held significant political power. Below them were the plebeians, free citizens with limited political influence, and the vast numbers of slaves who formed the backbone of the economy. The family unit was central, governed by the paterfamilias, the male head who held absolute authority.
Culturally, the Romans were eclectic, absorbing and adapting elements from the civilizations they encountered, particularly the Greeks. Roman art, literature, and philosophy reflected this synthesis, creating a rich cultural tapestry. Latin, the Roman language, became the lingua franca of the Western world, influencing numerous modern languages.
Roman architecture and engineering achievements were monumental. They perfected the arch, vault, and dome, constructing enduring structures like the Colosseum, Pantheon, and aqueducts. These engineering marvels not only showcased Roman ingenuity but also served practical purposes, from public entertainment to water supply.
Palestine last event orientationfvgnh .pptxRaedMohamed3
An EFL lesson about the current events in Palestine. It is intended to be for intermediate students who wish to increase their listening skills through a short lesson in power point.
Operation “Blue Star” is the only event in the history of Independent India where the state went into war with its own people. Even after about 40 years it is not clear if it was culmination of states anger over people of the region, a political game of power or start of dictatorial chapter in the democratic setup.
The people of Punjab felt alienated from main stream due to denial of their just demands during a long democratic struggle since independence. As it happen all over the word, it led to militant struggle with great loss of lives of military, police and civilian personnel. Killing of Indira Gandhi and massacre of innocent Sikhs in Delhi and other India cities was also associated with this movement.
Francesca Gottschalk - How can education support child empowerment.pptxEduSkills OECD
Francesca Gottschalk from the OECD’s Centre for Educational Research and Innovation presents at the Ask an Expert Webinar: How can education support child empowerment?
Welcome to TechSoup New Member Orientation and Q&A (May 2024).pdfTechSoup
In this webinar you will learn how your organization can access TechSoup's wide variety of product discount and donation programs. From hardware to software, we'll give you a tour of the tools available to help your nonprofit with productivity, collaboration, financial management, donor tracking, security, and more.
The French Revolution, which began in 1789, was a period of radical social and political upheaval in France. It marked the decline of absolute monarchies, the rise of secular and democratic republics, and the eventual rise of Napoleon Bonaparte. This revolutionary period is crucial in understanding the transition from feudalism to modernity in Europe.
For more information, visit-www.vavaclasses.com
Read| The latest issue of The Challenger is here! We are thrilled to announce that our school paper has qualified for the NATIONAL SCHOOLS PRESS CONFERENCE (NSPC) 2024. Thank you for your unwavering support and trust. Dive into the stories that made us stand out!
2. Democritus (460 - 370 BC)
Was the first person to come up with the idea
of atom
Believed that all matter was composed of
indivisible particles he called “ATOMS”
Which is derived from the Greek word
“Atomos” – meaning indivisible
He also believed that different atoms:
Are different sizes
Have different properties
Other philosophers of that time did not agree
with his theories.
3. John Dalton (1766-1844)
• Dalton is the “Father of
Atomic Theory”
• Dalton’s ideas were so
brilliant that they have
remained essentially
intact up to the present
time and has only been
slightly corrected.
4. Dalton’s Atomic Theory (1803)
aka: 5 Postulates
1. All matter is composed of extremely
small particles called atoms. (I agree with
Democritus!)
2. All atoms of a given element are
identical, having the same:
- size
- mass
- chemical properties.
3. All atoms of different elements are
different.
5. 4. Atoms cannot be created, divided
into smaller particles, or destroyed.
**In a chemical reaction, atoms of different elements are
separated, joined or rearranged. They are
never changed into the atoms of another element.
We will learn more later**
5. Atoms combine in definite whole
number ratios to make compounds
(you can’t have a ½ of a Carbon bonding with
Oxygen; it’s a whole atom or no atom)
Dalton’s Atomic Theory (1803)
aka: 5 Postulates
6. Dalton’s Atomic Model
•Based on Dalton’s Atomic
Theory (5 postulates), most
scientists in the 1800s
believed that the atom was like
a tiny solid ball that could
not be broken up into parts.
•Dalton was credited for the
three Atomic Laws that were
proven after his time.
7. Dalton’s Atomic Laws
1. Law of Conservation of
Mass
Matter cannot be created or
destroyed in any physical or
chemical process, just transferred.
2. Law of Constant Composition
When atoms combine to form molecules,
the ratio of atoms is constant.
Example – H2O will always have 2 times
as many Hydrogen atoms as Oxygen.
8. Dalton’s Atomic Laws
3. Law of Multiple Proportions – if two
elements can combine to form more than one
compound, then the ratio of the second element
combined with a certain mass of the first element
is always a ratio of small whole numbers.
Formula
Ratio of N:O
Example:
CO vs. CO2
10. JJ Thomson (1856-1940)
• Used cathode rays to
prove that Dalton’s Solid-
ball model could be
broken into smaller
particles
•Thomson is credited
with discovering
electrons
11. Cathode Ray Tubes
• Cathode rays had been used for
some time before Thompson’s
experiments.
• A cathode ray is a tube that has
a piece of metal, called an
electrode, at each end. Each
electrode is connected to a power
source (battery).
• When the power is turned on, the electrodes
become charged and produce a stream of charged
particles. They travel from cathode, across the tube
to the anode.
12. Cathode Ray Tubes
• Thomson put the tube
in a magnetic field.
He predicted that the
stream would travel in
a straight path.
• Instead, he found that
the path curved away
from a negatively
charged plate and
toward a positively
charged plate
• Why?
•Like charges repel each other,
and objects with unlike charges
attract each other, Thomson
concluded that the stream of
charged particles had electrons
in them.
++++++++++++++
-----------------------------
14. Cathode Ray Tube Experiment
•Thompson Concluded:
•Cathode rays are made up of
invisible, negatively charged
particles called Electrons.
•These electrons had to come from the matter (atoms)
of the negative electrode.
•Since the electrodes could be made from a variety of
metals, then all atoms must contain electrons!
15. Thomson’s Plum Pudding Model
•Thomson’s Plum Pudding model is a +
charge sphere that has (- )charged
electrons scattered inside, like “raisins” in
“plum pudding”.
•Overall, the atom is neutral atom because
the atom had the same number of
positive and negative charges.
•From Thomson’s experiments, scientists concluded that
atoms were not just neutral spheres, but somehow were
composed of electrically charged particles.
•The balance of positive and negative charge supports the
neutral atom.
16. Rutherford (1871-1937)
Took Thomson’s Plum
Pudding Model and added
to it
Used the “Gold Foil
Experiment” to discover the
existence of:
An atomic Nucleus
Protons (in later experiments)
You must be able to
explain the Gold Foil
Experiment…it will be on
the CST
17. Gold Foil Experiment
Rutherford directed a narrow
beam of alpha particles (+
charges) at a thin piece of
gold foil.
Based on observations from
other experiments involving
alpha particles, he predicted
that the (+) charges would
go through the foil
18. Results from Gold Foil Experiment
•Rutherford found that every
once and a while, a + particle
was deflected bounced back.
(about 1% of the time)
•Why?
•Because the + charge hit a
central mass of positive charge
and was repelled.
20. The Nuclear Model of the Atom
•To explain the results of the experiment,
Rutherford’s team proposed a new model of
the atom.
21. Conclusions from Rutherford’s
Gold Foil Experiment (memorize this!)
• The atom contains a positively charged
“nucleus”
•This nucleus contains almost all of the mass of
the atom, but occupies a very small volume of
the atom.
•The negatively charged electrons occupied
most of the volume of the atom.
• The atom is mostly empty space.
22. Rutherford’s Planetary Model
• To explain his
observations,
Rutherford developed
a new model
•The electrons orbit
the nucleus like the
planets revolve around
the sun.
23. Bohr (1885-1962)
Worked in Rutherford’s lab
Wondered why – electrons
are not attracted to the +
nucleus and cluster around
it
Disproved Rutherford’s
Planetary Model
Experimented with light and
its interaction with matter to
develop a new model.
24. Bohr’s Energy Level Model
Energy Level Model: Electrons are
arranged in circles around the
nucleus. Each circle has a different
energy.
•Electrons are in constant motion,
traveling around the circle at the
speed of light.
•Electrons can “jump” from one circle
to the next
•But they can’t go to the nucleus they
traveling too fast to be fully attracted.
25. Bohr’s Energy Level Model
• He proposed the following:
4. The electrons must absorb or emit a fixed
amount of energy to travel between these
energy levels
3. The electrons orbit the nucleus at fixed
energy levels.
2. Electrons can only be certain distances from
the nucleus.
1. Protons and neutrons are in the nucleus
26. Review
Who is the father of atomic theory?
Dalton
What was the first model of the atom?
Dalton’s Tiny Ball Model
What are Dalton’s 3 Laws?
Law of Conservation of Mass, Law of
Constant Composition, Law of Multiple
Porportion
27. Review
How were Thomson’s and Dalton’s model
different?
Dalton’s model was 1 sphere that cannot
be divided, Thomson had the plum pudding
where electrons are randomly spread
throughout a positively charged sphere.
What did Thomson find out?
Atoms have electrons, they have a - charge
28. Review
What were Rutherford’s conclusions from the
Gold Foil Experiment?
Atom has a positively charged nucleus
electrons are outside,
atoms are mostly empty
Nucleus contains most of the mass.