If all the elements are arranged in the order of their atomic weights, a periodic repetition of properties is obtained. This is expressed by the law of periodicity.— Dmitry Ivanovich Mendeleev
2. The chemical Bond: Electronic concept of valency. Different types of chemical bond e.g. ionic, covalent, coordinate covalent metallic, dipole, hydrogen bond etc. Theories of covalent bonding and hybridization.
2. The chemical Bond: Electronic concept of valency. Different types of chemical bond e.g. ionic, covalent, coordinate covalent metallic, dipole, hydrogen bond etc. Theories of covalent bonding and hybridization.
The chemical Bond: Electronic concept of valency. Different types of chemical bond e.g. ionic, covalent, coordinate covalent metallic, dipole, hydrogen bond etc. Theories of covalent bonding and hybridization.
A chemical bond is a lasting attraction between atoms that enables the formation of chemical compounds or substance . The bond may result from the electrostatic force of attraction between atoms with opposite charges, or through the sharing of electrons as in the covalent bonds........
The presentation "Chemical Bonding" is prepared for class IX. It contains a brief introduction to bonding and a detailed study of types of chemical bonds, basically ionic and covalent, along with the characteristics of compounds formed by these bonds.
All constructive comments are welcome.
If all the elements are arranged in the order of their atomic weights, a periodic repetition of properties is obtained. This is expressed by the law of periodicity.— Dmitry Ivanovich Mendeleev
The chemical Bond: Electronic concept of valency. Different types of chemical bond e.g. ionic, covalent, coordinate covalent metallic, dipole, hydrogen bond etc. Theories of covalent bonding and hybridization.
A chemical bond is a lasting attraction between atoms that enables the formation of chemical compounds or substance . The bond may result from the electrostatic force of attraction between atoms with opposite charges, or through the sharing of electrons as in the covalent bonds........
The presentation "Chemical Bonding" is prepared for class IX. It contains a brief introduction to bonding and a detailed study of types of chemical bonds, basically ionic and covalent, along with the characteristics of compounds formed by these bonds.
All constructive comments are welcome.
If all the elements are arranged in the order of their atomic weights, a periodic repetition of properties is obtained. This is expressed by the law of periodicity.— Dmitry Ivanovich Mendeleev
Second-level Digital Divide and experiences of Schools and TeachersLiwayway Memije-Cruz
The second-level digital divide, is referred to as the production gap, and it describes the gap that separates the consumers of content on the Internet from the producers of content.
Science and technology studies, or science, technology and society studies (STS) is the study of how society, politics, and culture affect scientific research and technological innovation, and how these, in turn, affect society, politics and culture.
A hydrocarbon is a molecule whose structure includes only hydrogen and carbon atoms. Hydrocarbons form bonds with other atoms in order to create organic compounds.
Hydrocarbon derivatives are based on simple hydrocarbon compounds that contain only hydrogens and carbons. Hydrocarbon derivatives contain at least one element other than hydrogen or carbon, such as oxygen, nitrogen or one of the halogen atoms (elements in column 7A of the Periodic Table.
Organic reactions are chemical reactions involving organic compounds. Organic reactions are used in the construction of new organic molecules. The production of many man-made chemicals such as drugs, plastics, food additives, fabrics depend on organic reactions.
Organic chemistry involves the study of the structure, properties, composition, reactions, and preparation of carbon-containing compounds, which include not only hydrocarbons but also compounds with any number of other elements, including hydrogen (most compounds contain at least one carbon–hydrogen bond), nitrogen, oxygen, halogens, phosphorus, silicon, and sulfur.
This branch of chemistry was originally limited to compounds produced by living organisms but has been broadened to include human-made substances such as plastics. The range of application of organic compounds is enormous and also includes, but is not limited to, pharmaceuticals, petrochemicals, food, explosives, paints, and cosmetics.
Organic chemistry is the study of the structure, properties, composition, reactions, and preparation of carbon-containing compounds, which include not only hydrocarbons but also compounds with any number of other elements, including hydrogen (most compounds contain at least one carbon–hydrogen bond), nitrogen, oxygen,
Science and technology studies, or science, technology and society studies (STS) is the study of how society, politics, and culture affect scientific research and technological innovation, and how these, in turn, affect society, politics and culture.
Isomers are molecules with the same molecular formula, but different structural or spatial arrangements of the atoms within the molecule. The reason there are such a colossal number of organic compounds which is more than 10 million is partly due to isomerism.
Apportionment is Apportionment involves dividing something up, just like fair division.
Voting is a method for a group, such as, a meeting or an electorate to make a collective decision or express an opinion, usually following discussions, debates or election campaigns.
Lipid metabolism entails the oxidation of fatty acids to either generate energy or synthesize new lipids from smaller constituent molecules. Lipid metabolism is associated with carbohydrate metabolism, as products of glucose (such as acetyl CoA) can be converted into lipids.
A Hamiltonian path is a path that visits each vertex of the graph exactly once.
A Hamiltonian circuit is a path that uses each vertex of a graph exactly once and returns to the starting vertex.
Carbohydrate metabolism involves the different biochemical processes responsible for the formation, breakdown, and interconversion of carbohydrates in living organisms.
A graph is a diagram displaying data which show the relationship between two or more quantities, measurements or indicative numbers that may or may not have a specific mathematical formula relating them to each other.
Every organism is composed of several different types of human body tissue. The human body tissue is another way of describing how our cells are grouped together in a highly organized manner according to specific structure and function. These groupings of cells form tissues, which then make up organs and various parts of the body.
Reproduction means producing offspring that may or may not be exact copies of their parents. It is a part of a life cycle, which is a series of events wherein individuals grow, develop, and reproduce according to a program of instructions encoded in DNA, which they inherit from their parents. When cells divide, each daughter cell receives a complete copy of DNA and enough cytoplasmic machinery to start up its own operation. DNA contains the blueprints for making different proteins.
.Enzymes are proteins that catalyze or speed up chemical reactions. They also help digest the foods we eat food and heal our wounds. They play major roles in respiration, making proteins, and DNA replication..
Salas, V. (2024) "John of St. Thomas (Poinsot) on the Science of Sacred Theol...Studia Poinsotiana
I Introduction
II Subalternation and Theology
III Theology and Dogmatic Declarations
IV The Mixed Principles of Theology
V Virtual Revelation: The Unity of Theology
VI Theology as a Natural Science
VII Theology’s Certitude
VIII Conclusion
Notes
Bibliography
All the contents are fully attributable to the author, Doctor Victor Salas. Should you wish to get this text republished, get in touch with the author or the editorial committee of the Studia Poinsotiana. Insofar as possible, we will be happy to broker your contact.
Richard's aventures in two entangled wonderlandsRichard Gill
Since the loophole-free Bell experiments of 2020 and the Nobel prizes in physics of 2022, critics of Bell's work have retreated to the fortress of super-determinism. Now, super-determinism is a derogatory word - it just means "determinism". Palmer, Hance and Hossenfelder argue that quantum mechanics and determinism are not incompatible, using a sophisticated mathematical construction based on a subtle thinning of allowed states and measurements in quantum mechanics, such that what is left appears to make Bell's argument fail, without altering the empirical predictions of quantum mechanics. I think however that it is a smoke screen, and the slogan "lost in math" comes to my mind. I will discuss some other recent disproofs of Bell's theorem using the language of causality based on causal graphs. Causal thinking is also central to law and justice. I will mention surprising connections to my work on serial killer nurse cases, in particular the Dutch case of Lucia de Berk and the current UK case of Lucy Letby.
Nutraceutical market, scope and growth: Herbal drug technologyLokesh Patil
As consumer awareness of health and wellness rises, the nutraceutical market—which includes goods like functional meals, drinks, and dietary supplements that provide health advantages beyond basic nutrition—is growing significantly. As healthcare expenses rise, the population ages, and people want natural and preventative health solutions more and more, this industry is increasing quickly. Further driving market expansion are product formulation innovations and the use of cutting-edge technology for customized nutrition. With its worldwide reach, the nutraceutical industry is expected to keep growing and provide significant chances for research and investment in a number of categories, including vitamins, minerals, probiotics, and herbal supplements.
What is greenhouse gasses and how many gasses are there to affect the Earth.moosaasad1975
What are greenhouse gasses how they affect the earth and its environment what is the future of the environment and earth how the weather and the climate effects.
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/
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.
Toxic effects of heavy metals : Lead and Arsenicsanjana502982
Heavy metals are naturally occuring metallic chemical elements that have relatively high density, and are toxic at even low concentrations. All toxic metals are termed as heavy metals irrespective of their atomic mass and density, eg. arsenic, lead, mercury, cadmium, thallium, chromium, etc.
2. Periodic Table
Periodic Table is the tabular arrangement of all the
chemical elements which are organized based on
atomic numbers, electronic configurations and
existing chemical properties.
3. Development of Periodic Table
As early as 1800, chemists
began to determine the atomic
weights of some elements with
fair accuracy. Several attempts
were made to classify the
elements on this basis.
4. State of the Environment:
Issues and Concerns
Johann Wolfgang Dobereiner
He classified the
elements in groups of 3
called triads, based on
similarities in properties
and that the atomic
mass of the middle
member of the triad was
approximately the
average of the atomic
masses of the lightest
elements.
5. John A. Newlands (1863)
He arranged the
elements in the order of
increasing atomic mass.
The eight elements
starting from a given
one is a kind of
repetition of the first like
the eight notes of the
octave of music and
called it the law of
octaves.
6. Lothar Meyer
He plotted a
graph showing
an attempt to
group elements
according to
atomic weight.
7. Dmitri Mendeleyeev (1869)
He worked out a
Periodic Table of
Elements were the
elements were
arranged in the order
of increasing atomic
weights with a regular
repetition (periodicity)
of physical and
chemical properties.
8. Henry Moseley
He arranged the
elements in the order of
increasing atomic
numbers, which relates
that the properties of the
elements are periodic
functions of their atomic
numbers. This is known
as the Modern Periodic
Law.
9. 1. Representative Elements are the elements in A Group/ Family. The term
representative element is related to stepwise addition of electrons to the s and p
sub levels of the atoms. Elements belonging to the same group or family have
similar properties.
2. Noble Gases or Inert Gases are the elements in the last group with completely filled
set of s and p orbitals.
3. Transition Elements are the elements in the columns IB - VIIIB which are called the
B Group/Family. Take note that they start with IIB up to VIIB, which have 3
columns and then end with IB and IIB. These sequences, which contain 10
elements each, are related to the stepwise addition of the 10 electrons to the d
sub level of the atoms. These elements are metallic-dense, lustrous, good
conductor of heat and electricity and in the most cases are hard. They form the
many colored compounds and form polyatomic ions like Mn04 and CrO4.
4. Inner Transition Elements are the 2 additional horizontal rows below composed of 2
groups of elements which were discovered to have similar characteristics as
Lanthanum in the 6th
period called Lathanoids (Rare Earth Metals) and Actinium
(Heavy Rare Elements). The Lanthanoids are all metals while the Actinoids are all
radioactive. All the elements after Uranium are produced artificially by nuclear
reactions.
Classification of elements in the
Periodic Table
10. Positions of metals, nonmetals and
metalloids in the Periodic Table
Metals are at the left and in the center of the Periodic Table. Atoms of
metals tend to donate electrons.
Nonmetals are at the far right and toward the top of the Periodic Table.
Atoms of non-metals tend to accept electrons.
Metalloids or borderline elements are elements that to some extent
exhibit both metallic and nonmetallic properties. They usually act as
electron donor with metals and electron acceptor with non-metals. These
elements lie in the zigzag line in the Periodic Table.
12. Exercise:
Consider the atoms of Period 3:
Na 2e 8e 1e Mg 2e 8e 2e Al 2e 8e 3e
Consider the electronic configuration of Group IA
elements:
Na 2e 8e 1e
K 2e 8e 8e 1e
Rb 2e 8e 18e 8e 1e
Cs 2e 8e 18e 18e 8e 1e
Fr 2e 8e 18e 18e 18e 8e 1e
13. When an atom losses or gains electron, it becomes a
positively/negatively charge particle called ion.
14. Ionization energy is the amount of energy required to remove the most
loosely bound electron in a gaseous atom or ion to give a positive (+) particle
of cation.
Going across a period, there is an increase in the
ionization energy due to the removal of electron in each
case is at the same level and there is a greater nuclear
charge holding the electron.
15. Electron affinity is the energy given off when a neutral gaseous
atom or ion takes in an electron. Negative ions or anions are formed.
16. Electronegativity is the tendency of an atom to attract shared
electrons to itself when it forms a chemical bond with another atom.