describe wat the atomic number of an element refers to.?
970267
it describes the # of protons & electrons in that element.
194958
The atomic number of nickel is 28 which is the number of electrons.  It is also the number of protons in its nucleus\n\nhttp://periodic.lanl.gov/default.htm\n\nhttp://en.wikipedia.org/wiki/Atomic_number
504733
The atomic number of an element is equal to the number of electrons it has. Do you mean something more than that?
783251
The number after an element is the number of atoms of that element.\n\nStart with NH4\nNH4 has:\n1 nitrogen\n4 hydrogen\n-----\nTotal of 5\n\nBecause it is in parentheses, that means there are multiple molecules of NH4... specifically 2 of them.\nThus (NH4)2 has 10 atoms (5 x 2).\n\nThen you have:\nCr2 --> 2 atoms of cromium\nO7 --> 7 atoms of oxygen\n\nAltogether you have 10 + 2 + 7 = 19 atoms in a molecule of (NH4)2Cr2O7
901095
They are arraigned in order of atomic number, that is, the number of protons in the nucleus of each element's atoms.
607033
The order of elements in the periodic table is determined by their atomic number, or number of protons (positively charged particles. The nucleus of the element is made up of protons and neutrons (neutral subatomic particles), and nearly all of the mass of the element resides here. \n\nElectrons "circle" the nucleus to even out the charge of the atom. The electrons organize themselves in layers, with a certain number of electrons in each layer. These layers are also referred to as the valence of the electron. The first layer has 2 electrons, the second and third have 8, the fourth has 18... These layers are what give the atom its volume.\n\nSince density is mass/volume, there isn't a linear relationship for density in each successive element, but the trend is density increases from left to right and top to bottom.
832813
atomic mass is, well the mass. also the number of protons + neutrons. Atomic number is the number of protons, which is also the number of electrons
890221
33 (also 33 electrons and this is the atomic number too)
213411
Atomic Number 3\nhttp://www.jergym.hiedu.cz/~canovm/vyhledav/varianty/litva.gif
287953
actually, it's arranged by the number of protons in the nucleus of an atom of each element, though the list in this song: http://www.privatehand.com/flash/elements.html\nis not.
214181
It is a table of all the atomic elements and the different building blocks of our world.\nThe periodic table is a table in which the chemical elements are arranged in order of their atomic numbers. With this arrangement, elements with similar chemical properties and electronic structures are displayed as vertical columns of the table.
450990
The mass of a nucleus indicates the number of protons and neutrons present in the nucleus. An element can have more than one isotope eg Carbon 12 and Carbon 14. The former has 6 protons and 6 neutrons, The latter 6 protons and 8 neutrons. \n\nThe atomic weight of an isotope refers to the numbers of protons AND neutrons present. The atomic number of an element refers to the number of protons in all its isotopes.\n\nHydrogen, though normally just a solo proton in its nucleus, does have two isotopes, deuterium, with 1 neutron, and tritium with two neutrons.\n\nA recent question asked about silver, how many of each in its nucleus. Its atomic number is 47, so clearly 47 protons. Naturally-occurring silver is given as having  an atomic weight of 108, so answerers answered 61 neutrons.\n\nHowever there is a subtlety they missed..\n\nNaturally-occurring silver is a mixture of Ag 107 (60 neutrons) and Ag 109 (62 neutrons). (Slightly more than 50% of the former.).\n\nSo the average atomic weight of the two isotopes is 108. But there is no Ag 108 isotope present. The wrong inference was drawn.\n\nSeveral people above are confusing atomic weight and atomic number, and what they each mean. So if you don't understand several of the answers it is because they are jumbled versions of the true picture.
965248
The atomic number (the big number in the middle or on top of the square) represents the number of protons in the atom, but since an atom is by definition neutral, the number of electrons is the same.  For an ion, you would take the atomic number and subtract the charge, so for instance, carbon (atomic # 12) with a +1 charge would have 11 electrons.
745796
s and p are orbitals. They also stand for the diffirenet blocks of the periodic table\nIts how you would show where an element is on the table and the electrons in its shells. for example:\nNitrogen\n1s^2 2s^2 2p^3\nthe first number says which period it is in, the letter is the block, and the power is how many elements into the block that is\n\nThis is a bit confusing hard to teach with just words
379019
The quantum number description of an electron *is* the electron, in a sense, so two electrons with the same quantum numbers would be the same electron.
46736
Find the number of protons. Then number of electrons = number of protons.
862578
well.. the atomic number for the nucleus is the number of protons inside of it.