Atoms, compounds, and ions

Chemistry is the study of matter, and all matter is made up of atoms. We will learn about elements, atomic number and mass, isotopes, moles (chemistry moles, not the animal), and compounds.
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In chemistry, we will often be thinking about the world on a much smaller scale than you can see with the naked eye. Here we will learn about atoms and elements, tiny particles that make up the world around us. What are atoms, and what kind of properties do they have? How do we weigh and count atoms? We will answer those questions in this section!

Atoms can lose or gain electrons to form ions, or combine in specific ratios to form compounds. In this tutorial we will learn about how ions and compounds are formed, visualized, and measured.

Anions and cations can combine to form ionic compounds such as sodium chloride (table salt) and and sodium bicarbonate (baking soda). In this tutorial, we will be learning how to name ions and ionic compounds from the formula, and how to find the formula from the compound name.

Learn how mass spectrometry can be used to detect isotopes, atoms of the same element with different numbers of neutrons.