For neutral atoms, the electron number is always the same as the proton number.
For ions, charged atoms, the proton number is different than the electron number by the charge (e.g. a hydrogen ion, H(+1) has 1 proton and 0 electrons, 1 more proton than electrons).
No. Total number of protons = total number of electrons and not total number of valence electrons.
Only for hydrogen and helium, total number of protons = total number of electrons = total number of valence electrons.
When the atom is electrically neutral (not an ion).
None. the positive charges on the 13 protons and the negative charges on the 13 electrons cancel each other out
Only for hydrogen and helium are these two numbers the same. All other elements have at least two non-valence electrons, and the total number of electrons must be equal to the number of protons. Therefore, in all elements except hydrogen and helium, the number of valence electrons is less than the number of protons.
12, the same as the number of protons indicated by magnesium having an atomic number of 12.
Sodium's atomic number is 11. To be neutral then, it must have 11 protons and 11 electrons. Since sodium is in group 1, it has 1 valence electron.
You should understand that while neutral atoms have the same number of protons and electrons, they do not usually have the same number of protons and valance electrons, because except for hydrogen and helium, atoms also have electrons in the inner shells, which are not valance electrons. Therefore, there is no atom which has 7 protons and 7 valance electrons, although there is an element that has 7 protons, and there are several elements that have 7 valence electrons.
No, the number of total electrons is equal to the number of protons.
Rarely. The number of valence electrons of an element depends on it's position on the periodic table. Any given element can have between 1-8 valence electrons. The number of valence electrons increases left to right on the periodic table, while the number of protons, which determine the atomic mass and identity of an element, increase in general. Therefore the number of valence electrons can only equal the number of protons at the 8th element and below (neon).
None. the positive charges on the 13 protons and the negative charges on the 13 electrons cancel each other out
YES!!!!
valence electrons
Only for hydrogen and helium are these two numbers the same. All other elements have at least two non-valence electrons, and the total number of electrons must be equal to the number of protons. Therefore, in all elements except hydrogen and helium, the number of valence electrons is less than the number of protons.
He has 2 valence electrons. Look on a periodic table. It will show He only has 2 protons and the number of protons and electrons is equal. It is an exception to the rule of group numbers corresponding to valence numbers.
12, the same as the number of protons indicated by magnesium having an atomic number of 12.
Elements in the same group have the same number of valence electrons. These are the outer-shell electrons that react with other elements.
Yes and no; the number of protons determine the valance number of electrons. The valence level of electrons and how full/empty it is largely determines an elements chemical behavior. I would say that valence electrons are the main determinant, but that is predetermined by protons.
Sodium's atomic number is 11. To be neutral then, it must have 11 protons and 11 electrons. Since sodium is in group 1, it has 1 valence electron.
In the neutral atom of a chemical element number of electrons= number of protons=atomic number.