Atom – the smallest particle of each element which bears its chemical properties. Both existence, and the structure of atom was a subject of reasonings and study since ancient times. It was established that the structure of atoms is similar to the structure of the Solar system: in the center the kernel which is taking very few place, but concentrated in itself almost all weight; around it "planets" - the electrons bearing negative charges rotate. And how it is possible to find an atomic nucleus charge?
Instruction
1. Any atom electrically is neutral. But, as electrons bear negative charges, they have to be counterbalanced by opposite charges. Indeed. Positive charges bear the particles under the name "protons" located in an atomic nucleus. Proton much massivny electron: it weighs as much how many 1836 electrons!
2. The simplest case – atom of hydrogen of the first element of the Periodic table. Having looked in the table, you make sure that he takes the place at the first number, and its kernel consists of the only proton around which the only electron rotates. It follows from this that the charge of an atomic nucleus of hydrogen is equal to +1.
3. Kernels of other elements consist already not only of protons, but also of so-called "neutrons". As you can easily understand from the name, neutrons do not bear any charge at all – neither negative, nor positive. Therefore remember: how many neutrons would not be a part of an atomic nucleus, they influence only its weight, but not a charge.
4. Therefore, size positively of a charge of an atomic nucleus depends only on that how many protons contain in it. But as as it was already specified, atom electrically is neutral, has to contain in its kernel as much protons how many electrons rotate around a kernel. The quantity of protons is defined by serial number of an element in Mendeleyev's Table.
5. Consider several elements. For example, the known and vital oxygen is in "cell" at number 8. Therefore, its kernel contains 8 protons, and the charge of a kernel will be +8. Iron occupies "cell" with number 26, and, respectively, has a charge of a kernel +26. And precious metal - gold, with serial number 79 - will have just the same charge of a kernel (79), with the sign +. Respectively, atom of oxygen contains 8 electrons, in iron atom – 26, and in gold atom – 79.