Brianna+Kelley-What+is+the+difference+between+an+atom,+molecule,+element,+isotope,+and+compound?

= Welcome to Brianna Kelley Wiki!! =

What is an atom?
=== An atom is the smallest unit of matter. It is the building block of matter. It is made out of protons, neutrons, and electrons. The size is 0.1-0.5 nanometers. Protons give off an positive charge, neutrons have no charge, and electrons have a negative charge. ===



A compound is a substance which has at least two elements that are combined by a bond.