A molecule is a set of chemically bonded atoms. The electric charge of the molecules is neutral.
There is a definition of an older molecule that is less general and less precise: "A molecule is the smallest pair of a substance that can have independent and stable existence while retaining its chemical properties and certain physicochemical properties." By this definition there could be molecules with a single atom. Types of molecules
Molecules can be formed in two different ways:
- Discrete molecules: molecules can be formed by a well defined number of atoms…
What is an atom? Imagine you have a piece of iron. The parts. You still have two pieces of iron but smaller. The you come from again ... Every time have smaller pieces until you reach a moment that if the seeming from what you would no longer be iron.
At this point what is left is an atom, an iron atom. Definition of atom
From a more formal way, we define as the smallest atom in an element can be divided without losing its chemical properties particle.
The origin of the word atom comes from the Greek, meaning indivisible. At the time that these particles were baptized…
To explain the history of nuclear energy we could distinguish three major stages:
- Physical and chemical scientific studies of the elements.
- The development of the nuclear bomb during World War II.
- Use of nuclear energy in the civil field.
Scientific studies cover this whole period since the first Greek philosophers began to define atoms, until the development of the first nuclear bomb. In this process, different scientists discover the presence of electrons, neutrons and protons and properties that make one atom more radioactive than another.…
Neutron moderator is a component part of the nuclear reactors. It is located in the reactor core. The function of the moderator is to reduce the speed of the neutrons in a nuclear fission reaction.
During nuclear reactions fission neutrons collide with fissile atoms (
Isotopes are atoms whose nuclei have the same number of protons but different numbers of neutrons. Not all atoms of the same element are identical and each of these varieties corresponds to a different isotope.
Each isotope of the same element have the same atomic number (Z) but each has a different mass number (A). The atomic number is the number of protons in the atomic nucleus of the atom. The mass number is the sum of neutrons and protons of the core. This means that different isotopes of the same atom differ from each other only by the number of neutrons.
The items that can…
Nuclear energy is the energy in the nucleus of an atom. Atoms are the smallest particles that can break a material. At the core of each atom there are two types of particles (neutrons and protons) that are held together. Nuclear energy is the energy that holds neutrons and protons.
Nuclear energy can be used to produce electricity. This energy can be obtained in two ways: nuclear fusion and nuclear fission. In nuclear fusion, energy is released when atoms are combined or fused together to form a larger atom. The sun produces energy like this. In nuclear fission, atoms are split into…
Nowadays, the main use given to nuclear energy is the generation of electric power. Nuclear power plants are responsible of doing this process. Almost all nuclear power plants in production are using nuclear fission since the nuclear fusion, despite being under development, is currently unfeasible.
The operation of a nuclear power plant is identical to the operation of a thermoelectric power plant operating with coal, oil or gas, except in the way of providing heat to the water for converting this one into steam. In nuclear reactors this process of producing heat is made by the fission…
An electron is a stable negatively charged elementary particle which is one of the fundamental components of the atom. For this reason it can also be defined as a subatomic particle. It is part of the group of leptons.
Electrons may appear in the free state (without being attached to any atom) or attached to the nucleus of an atom. There are electrons in atoms spherical layers of different radious. These spherical layers represent energy levels. The larger spherical shell, the greater the energy contained in the electron.
In the electrical conductors, the current flows results…
A nuclear power plant is a facility for obtaining electrical energy using nuclear energy.
Its operation is similar to that of a thermal power plant or that of a solar thermal plant: from a source of energy thermodynamics is used to obtain heat, with the heat to get steam and with the steam to drive a turbine that will generate electricity.
The difference between the different types of electrical installations is in the energy source: a nuclear power plant uses the heat released in the nuclear fission reactions of certain atoms, in a thermal power station the heat source (thermal…
Nuclear fusion is a nuclear reaction through which two light nuclei of atoms, usually hydrogen and its isotopes (deuterium and tritium), are combined forming a heavier nucleus. This binding is usually accompanied by the emission of particles (in case of deuterium nuclei one neutron is emitted). This nuclear fusion reaction releases or absorbs a lot of energy in the form of gamma rays and kinetic energy of the emitted particles.This large amount of energy transforms matter to a plasma state.
The nuclear fusion reactions can emit or absorb…