This document discusses the structure of atoms and the periodic table. It begins by introducing atomic theories proposed by scientists like Dalton, Thomson, Rutherford, Bohr and Schrodinger. It then discusses subatomic particles like protons, neutrons and electrons. The document explains how elements are organized on the periodic table based on their atomic number and electronic configuration. It provides examples of writing out electronic configurations and identifying protons, neutrons and electrons in different isotopes.
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”.
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”.
Matter Structure & Chemical & Physical changes, properties, and processes.Ospina19
A brief introduction to matter structure and how chemical and physical changes affect its properties in the processes described before. For more science information follow this link, which will take you to our blog; http://biologyblogvermont7.weebly.com
Matter Structure & Chemical & Physical changes, properties, and processes.Ospina19
A brief introduction to matter structure and how chemical and physical changes affect its properties in the processes described before. For more science information follow this link, which will take you to our blog; http://biologyblogvermont7.weebly.com
A brief history of discovery of structure of atoms - particles and rays, nuclear decays, radioactivity, X-ray production. For RADIATION ONCOLOGY students. Purely academic and non-commercial purpose.
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.
Attacking the TEKS: Focus on Atomic Theory presented by Jane Smith, ACT2 2010
This session will expose you to the new TEKS and College Readiness Standards. Ideas for sequencing and planning the unit will be shared along with tips for appropriate demos, labs, and assessments. The intended audience is for teachers with 3 or less years of experience or anyone who wants to delve deeper into the new standards.
Deep Behavioral Phenotyping in Systems Neuroscience for Functional Atlasing a...Ana Luísa Pinho
Functional Magnetic Resonance Imaging (fMRI) provides means to characterize brain activations in response to behavior. However, cognitive neuroscience has been limited to group-level effects referring to the performance of specific tasks. To obtain the functional profile of elementary cognitive mechanisms, the combination of brain responses to many tasks is required. Yet, to date, both structural atlases and parcellation-based activations do not fully account for cognitive function and still present several limitations. Further, they do not adapt overall to individual characteristics. In this talk, I will give an account of deep-behavioral phenotyping strategies, namely data-driven methods in large task-fMRI datasets, to optimize functional brain-data collection and improve inference of effects-of-interest related to mental processes. Key to this approach is the employment of fast multi-functional paradigms rich on features that can be well parametrized and, consequently, facilitate the creation of psycho-physiological constructs to be modelled with imaging data. Particular emphasis will be given to music stimuli when studying high-order cognitive mechanisms, due to their ecological nature and quality to enable complex behavior compounded by discrete entities. I will also discuss how deep-behavioral phenotyping and individualized models applied to neuroimaging data can better account for the subject-specific organization of domain-general cognitive systems in the human brain. Finally, the accumulation of functional brain signatures brings the possibility to clarify relationships among tasks and create a univocal link between brain systems and mental functions through: (1) the development of ontologies proposing an organization of cognitive processes; and (2) brain-network taxonomies describing functional specialization. To this end, tools to improve commensurability in cognitive science are necessary, such as public repositories, ontology-based platforms and automated meta-analysis tools. I will thus discuss some brain-atlasing resources currently under development, and their applicability in cognitive as well as clinical neuroscience.
A brief information about the SCOP protein database used in bioinformatics.
The Structural Classification of Proteins (SCOP) database is a comprehensive and authoritative resource for the structural and evolutionary relationships of proteins. It provides a detailed and curated classification of protein structures, grouping them into families, superfamilies, and folds based on their structural and sequence similarities.
Professional air quality monitoring systems provide immediate, on-site data for analysis, compliance, and decision-making.
Monitor common gases, weather parameters, particulates.
THE IMPORTANCE OF MARTIAN ATMOSPHERE SAMPLE RETURN.Sérgio Sacani
The return of a sample of near-surface atmosphere from Mars would facilitate answers to several first-order science questions surrounding the formation and evolution of the planet. One of the important aspects of terrestrial planet formation in general is the role that primary atmospheres played in influencing the chemistry and structure of the planets and their antecedents. Studies of the martian atmosphere can be used to investigate the role of a primary atmosphere in its history. Atmosphere samples would also inform our understanding of the near-surface chemistry of the planet, and ultimately the prospects for life. High-precision isotopic analyses of constituent gases are needed to address these questions, requiring that the analyses are made on returned samples rather than in situ.
Multi-source connectivity as the driver of solar wind variability in the heli...Sérgio Sacani
The ambient solar wind that flls the heliosphere originates from multiple
sources in the solar corona and is highly structured. It is often described
as high-speed, relatively homogeneous, plasma streams from coronal
holes and slow-speed, highly variable, streams whose source regions are
under debate. A key goal of ESA/NASA’s Solar Orbiter mission is to identify
solar wind sources and understand what drives the complexity seen in the
heliosphere. By combining magnetic feld modelling and spectroscopic
techniques with high-resolution observations and measurements, we show
that the solar wind variability detected in situ by Solar Orbiter in March
2022 is driven by spatio-temporal changes in the magnetic connectivity to
multiple sources in the solar atmosphere. The magnetic feld footpoints
connected to the spacecraft moved from the boundaries of a coronal hole
to one active region (12961) and then across to another region (12957). This
is refected in the in situ measurements, which show the transition from fast
to highly Alfvénic then to slow solar wind that is disrupted by the arrival of
a coronal mass ejection. Our results describe solar wind variability at 0.5 au
but are applicable to near-Earth observatories.
Comparing Evolved Extractive Text Summary Scores of Bidirectional Encoder Rep...University of Maribor
Slides from:
11th International Conference on Electrical, Electronics and Computer Engineering (IcETRAN), Niš, 3-6 June 2024
Track: Artificial Intelligence
https://www.etran.rs/2024/en/home-english/
This presentation explores a brief idea about the structural and functional attributes of nucleotides, the structure and function of genetic materials along with the impact of UV rays and pH upon them.
Nucleic Acid-its structural and functional complexity.
Unit iii the atom and the prediodic table (2)
1. Chemistry I Unit III The atom & the periodic table
Ms. Claudia Barahona
October 2014
2. Stage 3
•Development of atomic theories
•Subatomic particles
•Electron configuration
•Organization of elements on the
periodic table
•Periodic properties (trends):
–Atomic size
–Ionization energy
–Electronegativity
3. Activity 3.1 The atom
•What is the atom composed of?
•Composed by subatomic particles:
•Protons : p+
•Electrons: e-
•Neutrons: n
4. Subatomic particles
•Particles that are smaller than the atom.
•Protons and neutrons make up the nucleus of an atom.
Note: Amu (Atomic Mass Unit) is defined as one-twelfth of the mass of the carbon atom with six protons and six neutrons.
Name
Symbol
Elctrical charge
Mass (amu)
Proton
Electron
Neutron
n
Name
Symbol
Elctrical charge
Mass (amu)
Proton
p+
+1
1
Electron
e-
-1
0.000549
Neutron
n
0
1
5. •Atomic number:
Is equal to the number of p+ in an atom.
•Mass number:
Is equal to the number of p+ and n in
the nucleus of an atom.
•Atomic mass or atomic weight:
Weight average mass of all the
natural occuring isotopes of an element
Information in the periodic table
6. Smallest particle of an element that retains the characteristis of the element.
Atom
Atomic theories: Theories that try to explain the structure of the atom:
•Dalton
•Thomson
•Bohr
•Ruhtherford
•Schrodinger
7. •Decomposition process in which unstable atomic nuclei will spontaneously decompose to form nuclei with a higher stability, resulting in a release of high energy radiation. Radioactivity
8. Radioactivity
Benefits
Risk
Used in nuclear medicine.
Radiotheraphy
Irradiation
Can burn the surface of the skin.
In contact with cells in the body may cause genetics mutations.
Fire detective systems
Generates wastes which we do not know how to manage or destroy.
Nuclear power stations
•Ex: P-32 (Tx of Leukemia), C-14 (Radiocarbon dating), Au-198 (Liver imaging and carcinoma), I-123 (Thyroid, brain and porstate cancer).
9. Modern periodic table
•Period: Each horizontal row.
•Group/family: Each vertical column, this elements will have similar properties.
15. •Isotopes:
Are atoms of the same element that have different mass number but the same chemical behavior.
Atomic symbol for writing Isotopes: AZX X= chemical symbol for the element Z= Atomic number A= Mass number
16. •Atomic mass or atomic weight: Weight average
mass of all the natural occuring isotopes
of an element
•Atomic number: Is equal to the number
of protons in an atom. Information in the periodic table
18. Exercise # 1 Subatomic particles
•Is each of the following statements true or false?
If false, explain your reason.
a.Protons are heavier than electrons.
True
b. Protons are attracted to neutrons.
False. p+ are attracted to e-
c. Electrons are so small that they have no electrical charge.
False. e- have a -1 charge
d. The nucleus contains all the protons and neutrons of an atom.
True
19. Exercise # 2 Subatomic particles
•Using the periodic table, state the atomic number, number of protons, and number of electrons for an atom of each of the following elements:
Element
Atomic number
p+
e-
Nitrogen
Magnesium
Bromine
21. Subatomic particles
•Using the periodic table, state the atomic number, number of protons, and number of electrons for an atom of each of the following elements:
Element
Atomic number
p+
e-
Nitrogen
7
7
7
Magnesium
12
12
12
Bromine
35
35
35
22. Exercise # 3 Subatomic particles
•Consider an atom that has 79 electrons.
a.How many protons are in its nucleus?
b.What is its atomic number?
c.What is its name, and what is its symbol?
24. Subatomic particles
•Consider an atom that has 79 electrons.
a.How many protons are in its nucleus?
79
a.What is its atomic number?
79
a.What is its name, and what is its symbol?
25. Subatomic particles
•The number of protons gives atoms their identity.
•Atomic number (Z)
#of protons
•Mass number (A)
•#protons + #neutrons
26. Information in the periodic table
•Atomic mass or atomic weight: Weight average
mass of all the natural occuring isotopes
of an element.
27. •Isotopes:
Are atoms of the same element that have different mass number but the same chemical behavior.
Atomic symbol for writing Isotopes: AZX X= chemical symbol for the element Z= Atomic number A= Mass number
28. Identify protons and neutron in isotopes
State the number of p+, e- and n in each of the following isotopes of Carbon (C).
Exercise# 4
Isotopes
Isotope
Protons
Electrons
Neutrons
6
6
6
6
6
7
6
6
8
29. Identify protons and neutron in isotopes
Write the symbol for each of the following isotopes:
a)A nitrogen atom with 8 neutrons.
b)An atom with 20 protons and 22 neutrons.
c)An atom with mass number 27 and 14 neutrons.
Exercise# 5 Isotopes
31. Write the symbol for each of the following isotopes:
a)A nitrogen atom with 8 neutrons.
157N
a)An atom with 20 protons and 22 neutrons.
4220Ca
a)An atom with mass number 27 and 14 neutrons.
2713Al
Exercise# 5 Isotopes
33. Atomic theories
•Theories that try to explain the
structure of the atom.
–John Dalton
–J. J. Thomson
–Ernest Rutherford
–Niels Bohr
–Erwin Schrodinger
34. Evolution of the atomic theories
Billiard ball model- a small, solid sphere
35. Evolution of the atomic theories
Law of Conservation of mass:
States that the total mass present before a chemical reaction is the same as the total mass present after the chemical reaction; thus, mass is conserved. The law of conservation of mass was formulated by Antoine Lavoisier (1743-1794). This law was a result of his combustion.
36. Evolution of the atomic theories
Law of Constant composition or Law of definite proportions:
Formulated by Joseph Proust (1754-1826).
States that if a compound is broken down into its constituent elements, the masses of the constituents will always have the same proportions, regardless of the quantity or source of the original substance.
37. Evolution of the atomic theories Law of Constant composition or Law of definite proportions: Jon Berzelius did experiments with about 2000 compounds Berzelius prepared and purified the necessary reagents, developed the techniques to perform the analyses, and collected data on the relative weights of atoms of 43 elements. That confirmed John Dalton's atomic theory as well as Proust's law showing that separate elements always combined in whole-number proportions. *Also introduced the symbolism with which chemical formulas are still written
38. Evolution of the atomic theories
How was Dalton wrong in his proposal?
Not all atoms of the same element are exactly alike (isotopes).
Atoms are made up of subatomic particles.
39. J.J. Thomson
•Discovered the electron in a series of experiments using cathode-ray tube.
•In 1904 Thomson suggested a model of the atom as a sphere of positive matter in which electrons are positioned by electrostatic forces.
“Plum-pudding”
model
40. Ernest Rutherford
•Rutherford performed a series of experiments with radioactive alpha particles.
• He found that while most of the alpha particles passed right through the gold foil, a small number of alpha particles passed through at an angle (as if they had bumped up against
something) and some bounced straight
back
•Rutherford's experiments suggested
that gold foil, and matter in general, had
holes in it!
41. Niels Bohr
•Devised the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus— similar in structure to the solar system.
42. Erwin Schrodinger
•Schrödinger model describes the probability that an electron can be found in a given region of space at a given time. This model no longer tells us where the electron is; it only tells us where it might be.
•Introduced “wave
mechanics” as a
mathematical model.
45. Electronic configuration
Energy level: Specific energy that an electron has (bound by the electric field of the nucleus).
e- in the lower energy levels are usually closer to the nucleus.
Sublevel: Group of orbitals of equal energy within principal energy level.
Orbital: Region around the nucleus where e-s of a certain energy are more likely to be found. (s, p,d and f)
46. Electronic configuration
List of the number of electrons in each sublevel within an atom, arranged by increasing energy.
50. Electronic configuration
•To contruct the electronic configuration of an atom do the following:
1.Determine the number of electrons in the atom.
2.Put electrons moving from the lowest energy levels to the highest energy orbital available, starting with 1s (holds a maximum of two electrons).
3.Fill in the orbitals according to the number of electrons in the atom.
51. Electronic configuration
•Example: Write the electronic configuration of Lithium atom.
1.Electrons involved:
atomic number 3
2.Begin with the 1s sublevel.
1s2
3. Fill in the needed orbitals, until all the electrons are being positioned.
1s2 2s1
54. Electronic configuration
•Write the electron configuration for :
a.Nitrogen atom
1s2 2s2 2p3
b.Silicon atom
1s2 2s2 2p6 3s2 3p2
c. Chlorine atom
1s2 2s2 2p6 3s2 3p5
55. Electronic configuration
•List of the number of electrons in each sublevel within an atom, arranged by increasing energy.
•Chemistry book chapter 3 Pg 81
Orbital diagram
•Boxes represent the orbitals and half arrows represent electrons.
57. Aufbau´s principle
•e-s fill orbitals starting at the lowest available energy state before filling higher states (1s before 2s).
58. Pauli exclusion principle
•States the an orbital can hold up to maximum of 2 e-´s, which are seeing as spinning on its axis, which generates a magnetic field.
•An orbital can hold 0, 1, or 2 electrons only, and if there are two electrons in the orbital, they must have opposite (paired) spins.
59. Hund´s rule
•When filling sublevels other than s, electrons are placed in individual orbitals before they are paired up.
62. Valence electrons
•Electrons in the outermost energy level.
•Given by the group number (representative elements).
63. Valence electrons
•Electrons in the outermost energy level.
•Given by the group number (representative elements).
64. Oxidation number
•Shows the total number of e-´s which have been removed from an element (+) or added to an element (-).
65. Periodic trends
•Elctron configuration of atoms are an important factor in physical and chemical properties of the elements.
•Periodic properties increases or decreases across a period, and then the trend is repeated again in each successive group.
66. Periodic trends
•Electron afinity: The ability of an atom to attract additional electrons.
•Electronegativity: The relative ability of an element to attract electrons in a bond.
•Ionization energy: Energy needed to remove the least tight bound electron from an atom in gaseous (g) state.
•Atomic radius: Distance from the nucleus to the energy level that contains the valence (outermost) electrons.
68. Writing formulas
1.Identify the cation and anion or polyatomic ion.
2.Balance the charge.
3.Write the formula, cation first, using the subscript from the charge balance.
69. Subscripts in formulas
•The subscripts in the formula represent the number of positive and negative ions that give an overall charge of zero.
