In the nucleus
In the electron cloud
In the protons only
In the electrons only
The mass number
The atomic number
Their state of matter
Protons are positive but have no mass.
Protons are neutral with a mass of 1.
Electrons are negative and have no mass.
Electrons are positive and have no mass.
Neutrons are the same as protons
The mass must be rounded because you can not have 0.9 of a neutron.
The mass number is the same as the number of neutrons.
Sodium is not really an element since she can't find it on the periodic table.