Nucleus Of An Atom Describe The Composition Of The Nucleus

NUCLEUS OF AN ATOM Describe the composition of the nucleus of an atom The nucleus consists of neutrons (with a neutral charge and 1 mass) and protons (that have one positive charge and the same mass). Neutrons act as electrostatic 'glue' that binds the protons together(which would otherwise repel each other). The nucleus is orbited by electrons (that have negligible mass and one negative charge). This composition was proven by Rutherford's gold foil experiment Define proton number and nucleon number

Proton number (also called atomic number) The proton number is equal to the number of protons in the nucleus of an atom. The proton number is also equal to the number of electrons in orbit around a neutral atom.

Nucleon number (also called mass number) The nucleon number is equal to the total number of nucleons (protons and neutrons) in the nucleus of an atom.

Explain nuclide and its notation A type of atom specified by its atomic number, atomic mass, and energy state, such as carbon 14. It is a notation which gives you the number of protons and the mass of the nucleus in atomic units Usually number of Protons Z is given by the name of the nuclei and written as index . The mass number A is written as exponant From the mass number you can calculate number of neutrons using formula A=Z+N

Define istope An isotope is a form of a chemical element whose atomic nucleus contains a specific number of neutron s, in addition to the number of proton s that uniquely defines the element. The nuclei of most atom s contain neutrons as well as protons. (An exception is the common form of hydrogen, whose nucleus consists of a lone proton.) Every chemical element has more than one isotope. For any element, one of the isotopes is more abundant in nature than any of the others, although often multiple isotopes of a single element are mixed.

The isotope of an element is defined by the nucleon number, which is the sum of the number of protons and the number of neutrons in the atomic nucleus. The nucleon number is customarily written as a superscript preceding the chemical symbol for the element. For example, 16 O represents oxygen-16, which has 8 protons and 8 neutrons, while 12 C represents carbon-12, with 6 protons and 6 neutrons. These are the most common naturally occurring isotopes of oxygen and carbon, respectively. Some carbon-14 is found in nature. An atom of carbon-14 contains 6 protons and 8 neutrons and is denoted 14 C. Over time, 14 C decays into 12 C. Sometimes the isotope of an element is denoted by writing the nucleon number after the chemical symbol, and not as a superscript. Thus, some texts will denote carbon-14 as C-14 or C14 instead of 14 C. Certain isotopes of elements are unstable, giving off ionizing radiation, also known as radioactivity. Such an isotope is called a radioisotope. Carbon-14 is a radioisotope of carbon. In the case of an element that is radioactive in all its known forms, such as uranium (U), certain isotopes are more radioactive than others, and/or give off different proportions of the various types of ionizing radiation.

RADIOACTIVE DECAY State what radioactivity is 1. Spontaneous emission of radiation, either directly from unstable atomic nuclei or as a consequence of a nuclear reaction. 2. The radiation, including alpha particles, nucleons, electrons, and gamma rays, emitted by a radioactive substance.

Name common detectors for radioactive emissions

http://www.mpdocker.demon.co.uk/as_a2/topics/atomic_structure/proton_number.html http://education.yahoo.com/reference/encyclopedia/ http://dictionary.reference.com/browse/Nuclide?jss=1 http://answers.yahoo.com/question/ http://whatis.techtarget.com/definition/ http://www.pdfcoke.com/doc/18467527/Radioactivity