Photoelectric effect
... The Physics The cathode ray tube has a source of electrons (the cathode rays) which are accelerated using an electric potential difference and “steered” using coils. When the electrons collide with phosporus atoms on the screen photons in the visible region are produced. An x-ray tube works in the s ...
... The Physics The cathode ray tube has a source of electrons (the cathode rays) which are accelerated using an electric potential difference and “steered” using coils. When the electrons collide with phosporus atoms on the screen photons in the visible region are produced. An x-ray tube works in the s ...
幻灯片 1
... The attractive strong interaction between protons and neutrons is opposed by electrostatic repulsion between protons. Electrostatic repulsion force: among the protons. Repulsion dominates as Z increases and there is only a limited number of stable elements. ...
... The attractive strong interaction between protons and neutrons is opposed by electrostatic repulsion between protons. Electrostatic repulsion force: among the protons. Repulsion dominates as Z increases and there is only a limited number of stable elements. ...
Positronium: Review of symmetry, conserved quantities and decay
... mass of the system is approximately half that of hydrogen and the ‘‘atomic’’ energy levels 共neglecting fine and hyperfine structure effects, i.e., spin–orbit and spin–spin coupling, respectively兲 are likewise approximately half those of hydrogen. Hyperfine structure effects however, are far greater ...
... mass of the system is approximately half that of hydrogen and the ‘‘atomic’’ energy levels 共neglecting fine and hyperfine structure effects, i.e., spin–orbit and spin–spin coupling, respectively兲 are likewise approximately half those of hydrogen. Hyperfine structure effects however, are far greater ...
Pairing in a system of a few attractive fermions in a harmonic trap
... function of the distance x. At small distances the offdiagonal correlation is large and practically constant indicating a two-particle coherence. However, at distances comparable to the size of the correlated pair (compare fig. 3) the off-diagonal correlation falls down as expected, i.e. according to ...
... function of the distance x. At small distances the offdiagonal correlation is large and practically constant indicating a two-particle coherence. However, at distances comparable to the size of the correlated pair (compare fig. 3) the off-diagonal correlation falls down as expected, i.e. according to ...
Chemistry for the Pharmacy Technician
... charges. Thus salt is a sodium chloride compound consisting of both sodium (positive electrical charge) and chloride (negative electrical charge). The valence of an element is a number that represents its capacity to combine to form a molecule of a stable compound. An element can exist in various fo ...
... charges. Thus salt is a sodium chloride compound consisting of both sodium (positive electrical charge) and chloride (negative electrical charge). The valence of an element is a number that represents its capacity to combine to form a molecule of a stable compound. An element can exist in various fo ...
Balancing Reaction Equations Oxidation State Reduction
... Determining Oxidation Number of Elements & Compounds 1. In uncombined or free elements (not ionized), each atom has an oxidation number of 0. E.g., all of the atoms in these molecules: H2, Na, S8, O2, P4. 2. In simple ions (i.e., charged species which contain only one atom), the oxidation number ...
... Determining Oxidation Number of Elements & Compounds 1. In uncombined or free elements (not ionized), each atom has an oxidation number of 0. E.g., all of the atoms in these molecules: H2, Na, S8, O2, P4. 2. In simple ions (i.e., charged species which contain only one atom), the oxidation number ...
The hydrogen atom as an entangled electron–proton system
... which is diagonal and shows that the l eigenvalues are equal to l5 u c l u 2 . This also shows that the eigenvectors with zero eigenvalue do not participate in the expansion. The eigenvalues l are thus both the probabilities of finding subsystem u in the states u u l & and the probabilities of findi ...
... which is diagonal and shows that the l eigenvalues are equal to l5 u c l u 2 . This also shows that the eigenvectors with zero eigenvalue do not participate in the expansion. The eigenvalues l are thus both the probabilities of finding subsystem u in the states u u l & and the probabilities of findi ...
File
... radioactive series, secular and transient equilibrium. The nuclear atom, neutron-proton model of the atom, isotopes and their separation, neutron decay, -spectrum, the neutrino, electron capture and internal conversion; nuclear stability, stability lines, exotic nuclei. Standard , , and neutron ...
... radioactive series, secular and transient equilibrium. The nuclear atom, neutron-proton model of the atom, isotopes and their separation, neutron decay, -spectrum, the neutrino, electron capture and internal conversion; nuclear stability, stability lines, exotic nuclei. Standard , , and neutron ...
mark scheme - A-Level Chemistry
... Chemical error = 0/2 for (b)(ii) if other types of bonding or IMF mentioned. ...
... Chemical error = 0/2 for (b)(ii) if other types of bonding or IMF mentioned. ...
Voltage-tunable ferromagnetism in semimagnetic quantum dots with
... Now we can estimate the precision of the perturbation theory: ␦E0 / Eb is about a few percent for the typical parameters of the problem, which will be specified below. The precision is high because of the orthogonality of the spatial harmonic-oscillator functions n,n⬘共r兲. For example, the nonzero m ...
... Now we can estimate the precision of the perturbation theory: ␦E0 / Eb is about a few percent for the typical parameters of the problem, which will be specified below. The precision is high because of the orthogonality of the spatial harmonic-oscillator functions n,n⬘共r兲. For example, the nonzero m ...
- StarBooks
... Dalton's Atomic Theory All substances are made up of tiny, indivisible particles called atoms. Atoms of the same element are identical in shape, size, mass and other properties. Atoms of different elements are different in all respects. Atom is the smallest unit that takes part in chemical combinati ...
... Dalton's Atomic Theory All substances are made up of tiny, indivisible particles called atoms. Atoms of the same element are identical in shape, size, mass and other properties. Atoms of different elements are different in all respects. Atom is the smallest unit that takes part in chemical combinati ...
3. chemical bonding and molecular structure
... Generally, the ion, (cation or anion) with smaller size and more charge will have greater lattice energy. Born-Haber's cycle: The basis for Born-Haber's cycle is Hess's law. It states that the heat energy change will remain constant whether a chemical reaction occurs in one step or several steps. ...
... Generally, the ion, (cation or anion) with smaller size and more charge will have greater lattice energy. Born-Haber's cycle: The basis for Born-Haber's cycle is Hess's law. It states that the heat energy change will remain constant whether a chemical reaction occurs in one step or several steps. ...
syllabus 2014
... Internal resistance of a cell, potential difference and emf of a cell, combination of cells in series and in parallel. Kirchhoff’s laws and simple applications. Wheatstone bridge, metre bridge. Potentiometer-principle and applications to measure potential difference, and for comparing emf of two cel ...
... Internal resistance of a cell, potential difference and emf of a cell, combination of cells in series and in parallel. Kirchhoff’s laws and simple applications. Wheatstone bridge, metre bridge. Potentiometer-principle and applications to measure potential difference, and for comparing emf of two cel ...
LHCC - uniud.it
... huge baryon-antibaryon asimmetry in the Universe (NB today 1079!) • For practical purposes, we will assume that baryon and lepton nr are conserved, even if there is no deep theoretical reasons to suppose this conservation rule as absolute. • While total lepton number seems to be conserved, weak tr ...
... huge baryon-antibaryon asimmetry in the Universe (NB today 1079!) • For practical purposes, we will assume that baryon and lepton nr are conserved, even if there is no deep theoretical reasons to suppose this conservation rule as absolute. • While total lepton number seems to be conserved, weak tr ...
CHAPTER 9 CHEMICAL BONDING I
... individual atoms can complete their octets. The octet rule works mainly for elements in the second period of the periodic table. These elements have only 2s and 2p subshells, which can hold a total of eight electrons. When an atom of one of these elements forms a covalent compound, it can attain the ...
... individual atoms can complete their octets. The octet rule works mainly for elements in the second period of the periodic table. These elements have only 2s and 2p subshells, which can hold a total of eight electrons. When an atom of one of these elements forms a covalent compound, it can attain the ...
Electron configuration
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. For example, the electron configuration of the neon atom is 1s2 2s2 2p6.Electronic configurations describe electrons as each moving independently in an orbital, in an average field created by all other orbitals. Mathematically, configurations are described by Slater determinants or configuration state functions.According to the laws of quantum mechanics, for systems with only one electron, an energy is associated with each electron configuration and, upon certain conditions, electrons are able to move from one configuration to another by the emission or absorption of a quantum of energy, in the form of a photon.Knowledge of the electron configuration of different atoms is useful in understanding the structure of the periodic table of elements. The concept is also useful for describing the chemical bonds that hold atoms together. In bulk materials, this same idea helps explain the peculiar properties of lasers and semiconductors.