48 relations: Antonius van den Broek, Atom, Atomic mass, Atomic nucleus, Atomic number, Atomic theory, Bohr model, Charge number, Chemical bond, Chemical element, Discovery of the neutron, Dmitri Mendeleev, Effective atomic number, Electric charge, Electron, Electron configuration, Electron shell, Eric Scerri, Ernest Rutherford, German language, Hafnium, Half-life, Henry Moseley, History of the periodic table, Hydrogen, Iodine, Island of stability, Isotope, James Chadwick, Lanthanide, Lanthanum, Lutetium, Mass number, Monoisotopic element, Moseley's law, Neutron number, Nuclear reaction, Periodic table, Proton, Prout's hypothesis, Quantum mechanics, Relative atomic mass, Rutherford model, Spectral line, Tellurium, Thomas Royds, Unified atomic mass unit, X-ray tube.
Antonius Johannes van den Broek (4 May 1870, Zoetermeer – 25 October 1926, Bilthoven) was a Dutch amateur physicist notable for being the first who realized that the number of an element in the periodic table (now called atomic number) corresponds to the charge of its atomic nucleus.
An atom is the smallest constituent unit of ordinary matter that has the properties of a chemical element.
The atomic mass (ma) is the mass of an atom.
The atomic nucleus is the small, dense region consisting of protons and neutrons at the center of an atom, discovered in 1911 by Ernest Rutherford based on the 1909 Geiger–Marsden gold foil experiment.
The atomic number or proton number (symbol Z) of a chemical element is the number of protons found in the nucleus of an atom.
In chemistry and physics, atomic theory is a scientific theory of the nature of matter, which states that matter is composed of discrete units called atoms.
In atomic physics, the Rutherford–Bohr model or Bohr model or Bohr diagram, introduced by Niels Bohr and Ernest Rutherford in 1913, depicts the atom as a small, positively charged nucleus surrounded by electrons that travel in circular orbits around the nucleus—similar to the structure of the Solar System, but with attraction provided by electrostatic forces rather than gravity.
Charge number (z) refers to a quantized value of electric charge, with the quantum of electric charge being the elementary charge, so that the charge number equals the electric charge (q) in coulombs divided by the elementary-charge constant (e), or z.
A chemical bond is a lasting attraction between atoms, ions or molecules that enables the formation of chemical compounds.
A chemical element is a species of atoms having the same number of protons in their atomic nuclei (that is, the same atomic number, or Z).
Christmas is an annual festival commemorating the birth of Jesus Christ,Martindale, Cyril Charles.
The Christmas season, also called the festive season, or the holiday season (mainly in the U.S. and Canada; often simply called the holidays),, is an annually recurring period recognized in many Western and Western-influenced countries that is generally considered to run from late November to early January.
Christmas Eve is the evening or entire day before Christmas Day, the festival commemorating the birth of Jesus.
Christmas traditions vary from country to country.
The discovery of the neutron and its properties was central to the extraordinary developments in atomic physics that occurred in the first half of the 20th century.
Dmitri Ivanovich Mendeleev (a; 8 February 18342 February 1907 O.S. 27 January 183420 January 1907) was a Russian chemist and inventor.
Effective atomic number has two different meanings: one that is the effective nuclear charge of an atom, and one that calculates the average atomic number for a compound or mixture of materials.
Electric charge is the physical property of matter that causes it to experience a force when placed in an electromagnetic field.
The electron is a subatomic particle, symbol or, whose electric charge is negative one elementary charge.
In atomic physics and quantum chemistry, the electron configuration is the distribution of electrons of an atom or molecule (or other physical structure) in atomic or molecular orbitals.
In chemistry and atomic physics, an electron shell, or a principal energy level, may be thought of as an orbit followed by electrons around an atom's nucleus.
Eric R. Scerri is a chemist, writer and philosopher of science, of Maltese origin.
Ernest Rutherford, 1st Baron Rutherford of Nelson, HFRSE LLD (30 August 1871 – 19 October 1937) was a New Zealand-born British physicist who came to be known as the father of nuclear physics.
German (Deutsch) is a West Germanic language that is mainly spoken in Central Europe.
Hafnium is a chemical element with symbol Hf and atomic number 72.
Half-life (symbol t1⁄2) is the time required for a quantity to reduce to half its initial value.
Henry Gwyn Jeffreys Moseley (23 November 1887 – 10 August 1915) was an English physicist, whose contribution to the science of physics was the justification from physical laws of the previous empirical and chemical concept of the atomic number.
The periodic table is an arrangement of the chemical elements and are organized on the basis of their atomic numbers, electron configurations and recurring chemical properties.
Hydrogen is a chemical element with symbol H and atomic number 1.
Iodine is a chemical element with symbol I and atomic number 53.
In nuclear physics, the island of stability is the prediction that a set of heavy nuclides with a near magic number of protons and neutrons will temporarily reverse the trend of decreasing stability in elements heavier than uranium.
Isotopes are variants of a particular chemical element which differ in neutron number.
Sir James Chadwick, (20 October 1891 – 24 July 1974) was an English physicist who was awarded the 1935 Nobel Prize in Physics for his discovery of the neutron in 1932.
The lanthanide or lanthanoid series of chemical elements comprises the 15 metallic chemical elements with atomic numbers 57 through 71, from lanthanum through lutetium.
Lanthanum is a chemical element with symbol La and atomic number 57.
Lutetium is a chemical element with symbol Lu and atomic number 71.
The mass number (symbol A, from the German word Atomgewichte (atomic weight), also called atomic mass number or nucleon number, is the total number of protons and neutrons (together known as nucleons) in an atomic nucleus. It determines the atomic mass of atoms. Because protons and neutrons both are baryons, the mass number A is identical with the baryon number B as of the nucleus as of the whole atom or ion. The mass number is different for each different isotope of a chemical element. This is not the same as the atomic number (Z) which denotes the number of protons in a nucleus, and thus uniquely identifies an element. Hence, the difference between the mass number and the atomic number gives the number of neutrons (N) in a given nucleus:. The mass number is written either after the element name or as a superscript to the left of an element's symbol. For example, the most common isotope of carbon is carbon-12, or, which has 6 protons and 6 neutrons. The full isotope symbol would also have the atomic number (Z) as a subscript to the left of the element symbol directly below the mass number:. This is technically redundant, as each element is defined by its atomic number, so it is often omitted.
A monoisotopic element is one of 26 chemical elements which have only a single stable isotope (nuclide).
Moseley's law is an empirical law concerning the characteristic x-rays that are emitted by atoms.
The neutron number, symbol N, is the number of neutrons in a nuclide.
New Year is the time or day at which a new calendar year begins and the calendar's year count increments by one.
New Year's Day, also called simply New Year's or New Year, is observed on January 1, the first day of the year on the modern Gregorian calendar as well as the Julian calendar.
In the Gregorian calendar, New Year's Eve (also known as Old Year's Day or Saint Sylvester's Day in many countries), the last day of the year, is on 31 December which is the seventh day of Christmastide.
In nuclear physics and nuclear chemistry, a nuclear reaction is semantically considered to be the process in which two nuclei, or else a nucleus of an atom and a subatomic particle (such as a proton, neutron, or high energy electron) from outside the atom, collide to produce one or more nuclides that are different from the nuclide(s) that began the process.
The periodic table is a tabular arrangement of the chemical elements, ordered by their atomic number, electron configuration, and recurring chemical properties, whose structure shows periodic trends.
Prout's hypothesis was an early 19th-century attempt to explain the existence of the various chemical elements through a hypothesis regarding the internal structure of the atom.
Quantum mechanics (QM; also known as quantum physics, quantum theory, the wave mechanical model, or matrix mechanics), including quantum field theory, is a fundamental theory in physics which describes nature at the smallest scales of energy levels of atoms and subatomic particles.
Relative atomic mass (symbol: A) or atomic weight is a dimensionless physical quantity defined as the ratio of the average mass of atoms of a chemical element in a given sample to one unified atomic mass unit.
The Rutherford model is a model of the atom devised by Ernest Rutherford.
A spectral line is a dark or bright line in an otherwise uniform and continuous spectrum, resulting from emission or absorption of light in a narrow frequency range, compared with the nearby frequencies.
Tellurium is a chemical element with symbol Te and atomic number 52.
Thomas Royds (April 11, 1884 – May 1, 1955) was a Solar physicist who worked with Ernest Rutherford on the identification of alpha radiation as the nucleus of the helium atom, and who was Director of the Kodaikanal Solar Observatory.
The unified atomic mass unit or dalton (symbol: u, or Da) is a standard unit of mass that quantifies mass on an atomic or molecular scale (atomic mass).
An X-ray tube is a vacuum tube that converts electrical input power into X-rays.
2018 has been designated as the third International Year of the Reef by the International Coral Reef Initiative.
2019 (MMXIX) will be a common year starting on Tuesday of the Gregorian calendar, the 2019th year of the Common Era (CE) and Anno Domini (AD) designations, the 19th year of the 3rd millennium, the 19th year of the 21st century, and the 10th and last year of the 2010s decade.