The mass number
Because the more atoms there are, the more mass there is.
yes atoms do double in size however atoms in helium are smaller because oxygen atoms double in size.
The number of electron shells is higher.
Because they have many electron shells.
From left to right in a period the size of the atoms decreases.
is it true the size of a mmole of atoms has a reasonable mass
The atoms increase in size, because they gain more electron energy shells.
Even a single atom (if it is the right kind of atom) can generate a magnetic field, so there can be any number of atoms in a magnet, from one onwards to very large numbers, such as 1025.
Molecules are larger than atoms. A molecule is formed when two or more atoms bond together, creating a more complex structure. While atoms are the basic building blocks of matter, molecules can consist of different atoms or the same type of atom bonded together, resulting in a greater size and complexity.
Heat makes atoms/molecules vibrate more. This means that they take up more space - this means the item expands in size.
More or less, but all atoms are about the same size as each other. You would think that heavy atoms, with many electrons, would be much larger, but they aren’t. The reason is that large atoms have large nuclei with many protons. These exert a strong force on theelectrons, pulling them in closer. So even though there are more electrons in large atoms, they arepulled in closer, leaving the overall size of the heavy atoms the same as for light ones.
no