A group (also known as a family) is a vertical column in the Periodic Table of the chemical elements and the group number tells you what group it is in.
The atomic number is the number of protons in an atom's nucleus.
Atoms in the same group have similar structures.
number of each atom
The number of protons in the nucleus of an atom tell you which element you are dealing with. It is the number of protons in an atomic nucleus that determines the elemental identity. Only that. The atomic number of an element is the number of protons you will find in the nucleus of every atom of that element, regardless of the number of neutrons or electrons involved.
They tell you how often an atom - or a group of atoms - are repeated.
the group number,element in some way describes the number of valence electrons or the property that they exhibit
Tell you the number of protons and electrons in an atom
the atomic number is the number of protons/electrons in the atom
the atomic number is the number of protons/electrons in the atom
The mass number tells us the number (the sum) of protons and neutrons in the nucleus of an atom.
It would tell you how many neutrons make up the Nucleus of the atom.
The atomic number is the number of protons in an atom's nucleus.
Atoms in the same group have similar structures.
The mass number of an atom is equal to the sum of its number of protons and neutrons, simply, nucleons.
The mass number of an atom is equal to the sum of its number of protons and neutrons, simply, nucleons.
It would tell you how many neutrons make up the Nucleus of the atom.
If you are referring to GROUP NUMBER when you say "Roman numeral above the group", it tells you the number of valence electrons, or the number of outermost electrons, with transition metals being the exception. For group number XII - XVIII the number of valence electrons is the group number minus 10 (minus 10 for the 10 transition groups).