Maybe it's from the atomic weight? Maybe someone thinked of a formula stating that the atomic number came from the atomic weight with this formula:
Legend: A.W. is atomic weight while A.N. is atomic number.
A.W. (cancel all decimal places)
divided by:
2
= Atomic number.
I tried this, my own "experimental" formula whether it works. It worked accurately with oxygen and carbon, but in other elements, (try with krypton) it won't work. The quotient wasn't the atomic number in the Periodic Table of Elements, and I think the reason is that Krypton and other unequal A.N. elements belong in different groups are because they naturally need to be in a certain family or group. When I used the formula with krypton, it had the A.N. of 42, in the metals. Unfortuantely, krypton SHOULD belong to the non-metals.
I am searching for the truth if this formula is to be true. I have to prove this quick though, I need help in my never-ending researching. Thanks!
2006-08-26 01:25:07 · 4 answers · asked by Sp()oNg3Y::V.3.[] 3 in Science & Mathematics ➔ Chemistry
chemists now get the atomic number of an element by looking at a periodic table. they originally got it by counting the number of protons in an atom..
2006-08-26 01:35:22 · answer #1 · answered by Anonymous · 2⤊ 1⤋
The atomic number is the number of protons in the nucleus. The atomic mass is the addition of the protons and neutrons. The stomic number is also the number of electrons in an atom that is not combined. There is no formula to determine the atomic number from the atomic mass because the number of neutrons varies with isotopes.Elements can have a number of isotopes. As the elements get larger, they have more neutrons per proton. Hydrogen can weigh 1, 2, or 3. Carbon can be 12 or 14 and 13 has been seen. The mass given on the periodic table is a weighted average(amount available) of the known isotopes.
2006-08-26 02:31:57 · answer #2 · answered by science teacher 7 · 0⤊ 0⤋
The atomic number is the number of protons in the nucleus, which is the same for all atoms of a given element and must be a whole number. The atomic weight is the number of protons plus the number of neutrons. The number of neutrons can vary among different atoms of the same element (these are called isotopes). The atomic weight given in a periodic table is an average of all the possible weights for a given element based on the proportion of each isotope (there are actually two different systems for calculating average atomic weight, which is why you may see different values in different tables).
2006-08-26 01:38:55 · answer #3 · answered by stevewbcanada 6 · 0⤊ 0⤋
Number of protons in an element is the atomic number.
2006-08-26 01:32:14 · answer #4 · answered by descartesprotege 3 · 0⤊ 0⤋