Tip 1: How to determine the radius of the atom

Under radius atom mean distance between the nucleus of the atom and its outermost electron orbit.To date, the standard unit of measurement is the atomic radius of picometers (pm).To determine the radius of the atom very easily.
you need
  • Periodic table
first thing at hand should be regular periodic table, which are arranged in order of all the chemical elements known to mankind.Find this table is very easy in any reference book on chemistry, school textbook, or it can be purchased separately, in the nearest bookstore.
in the upper right corner of each of the chemicals listed its serial number.This number is identical with the atomic radius of atom .
For example, the serial number of chlorine (Cl) - 17. This means that the distance from the nucleus of an atom chlorine to the farthest orbit of its stable movement of the electron is 17 pm.If you want to find not only the atomic radius, but also the distribution of electrons in the electron orbits, thes
e data can be stress from the column of numbers to the right of the name of the chemical element.

Tip 2: How to determine the radius of the nucleus

The structure of the planet Earth isolated core, mantle and crust.The nucleus - the central part located furthest from the surface.Mantle is located beneath the crust and above the core .Finally, the cortex - the outer hard shell of the planet.
How to determine the radius of the nucleus
One of the first suggested the existence core British chemist and physicist Henry Cavendish in the XVIII century.He was able to calculate the mass and density of the Earth's average.He compared the density of the Earth with a density of rocks on the surface.It has been found that the surface density is significantly lower than the average.
German seismologist E. Wiechert proved the existence core of the Earth in 1897.American geophysicist B. Gutenberg in 1910 defined the depth of the core - 2900 km.According to scientists, the core consists of an alloy of iron, nickel and other elements that have an affinity for iron, gold, carbon, cobalt, germanium, and others.
Middle radius core is 3500 kilometers.In addition, the structure of the nucleus Earth's solid inner core is isolated, having radius of about 1300 kilometers, and the liquid outer radius om about 2200 kilometers.In the center of core temperature reaches 5000 ° C.The mass of the nucleus estimated at nearly 2 • 10 ~ 24 kg.
can draw an analogy between the structure of the planets and the structure of the atom.The atom is also highlighted the central part - the core, and in the core of the great bulk.The dimensions of nuclei are a few femtometrov (from the Latin. Femto - 15).The prefix "femto" means multiplication by ten to the minus fifteenth.Thus, the nucleus of an atom of 10 thousand times smaller than the atom itself, and 10 ~ 21 times smaller than the nucleus Earth.
To evaluate the radius of the planet, use indirect geochemical and geophysical methods.In the case of an atom are analyzing decay of heavy nuclei, taking into account not only the geometric radius , as radius of the nuclear forces.The idea of ​​planetary structure of the atom proposed by Rutherford.The dependence of the mass of the nucleus from range and is not linear.
Because of the periodic table, it is very easy to find not only the atomic radius and atomic weight, molecular weight, period and number of an element, as well as distributionelectrons in the electron orbits with the number of orbits.
most popular model of the atom is a model adopted in 1913 by Niels Bohr.It is also known as the planetary model.This is due to the fact that electrons, like the planets of the solar system, moving around the Sun - the nucleus of the atom.The orbits of the electrons are constant.The development of this model gave rise to the development of a new direction in theoretical physics - quantum mechanics.
The first orbital radius of the electron is called the Bohr radius, and the energy of the electrons in the first orbit is called the ionization energy of the atom.
Helpful Hint
should be noted that the radius of any atom is inversely proportional to the number of protons in its nucleus, and equal to the charge of its nucleus.
  • how the atomic radius