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Science (grade 7) Atoms and Periodic table study guide
A positive charged atom
An atom with no charge(neutral)
A negative charged atom
Atomic Mass Unit
The SI unit used to express the masses of particles in atoms
The number of protons in the nucleus of an atom
The weighted average of the masses of all the naturally occurring isotopes of that element.
Atoms that have the same number of protons but have different numbers of neutrons
When you add or loose electrons
Happening at regular intervals
Law states that the repeating chemical and physical properties of elements change periodically with the elements atomic numbers
Each horizontal row of elements(from left to right) on the periodic table
Each vertical column of elements(from top to bottom) on the periodic table