Atom Worksheets

What are the Parts of an Atom?

Atom is the most basic unit of matter. It has a dense nucleus with a cloud of negatively charged electrons surrounding it. Here are the parts of an Atom: Electron; it is a subatomic particle with a negative electrical charge. The mass of an electron is so small that it is generally not even considered. Nucleus; the dense center of an atom containing neutrons and protons. Neutron; it is a subatomic particle within the nucleus of an atom that has a neutral charge. Proton; a subatomic particle inside the nucleus of an atom with a positive charge. All three subatomic particles have mass. Protons and neutrons have what is considered one atomic mass unit, but the electron has a lot less mass. In fact it has one-thousandths an atomic unit. Because of their opposite charges electrons and protons are attracted to one another holding the nucleus together somewhat. Because of the even charges, atoms are electrically neutral. If an atom looses or gains an electron, it becomes an ion. Due to the uneven charges, they are considered ions and have an overall negative or positive charge.

Parts of a 3-Dimensional Atom

Name all the parts of the atom and answer questions like: How many protons does this atom have?


Parts of a 2-Dimensional Atom

Name the structures and describe their charge.


Molecule Models: Model to Formula

Using the model key for each element, write the chemical formula for each molecule.


Molecule Models: Formula to Model

Using the model key for each element, draw the model of each molecule.


Periodic Table of Elements Activity

We provide you with a completed table as a reference to complete worksheets that contain missing information.




Using the Periodic Table of Elements

Use the Periodic Table of Elements and your knowledge of chemistry to complete the blanks for each element. Round the atomic mass to the nearest whole number.