The Structure of Atoms
The Bohr model of the atom says that electrons are like little planets orbiting around the nucleus, much like the Earth does around the sun. An electron is a tiny, negatively charged particle. As you will learn later, it is responsible for chemical bonding. Almost all of the properties of an atom relate to electrons. They're important!
The nucleus, or center part, of the atom contains both protons and neutrons. Protons are positively charged, meaning that it's kind of like one end of a magnet that will attract negatively charged things (like electrons!). Neutrons are neutral. This means that they do not have a charge. Atoms with more neutrons tend to be more stable than atoms with fewer neutrons. This is because protons repel each other (like magnets repel when you try to put two north poles together). Neutrons basically interrupt these repulsions, helping the nucleus stick together.
If this did happen—if protons and electrons stuck together in one big ball—our entire world would be different. In fact, it would be so different that it might not be able to exist. You see, if electrons stuck to protons, atoms would be less chemically reactive. This would make complex chemical structures like plastic or hemoglobin or even simple structures like oxygen impossible. We would not be able to survive, and the universe would not be able to stick together. So what is it?
Editors: Emily Zhang
Image sources: (1) screenshot, "The Powers of Ten", (2) compiled from original and public domain images, (3) public domain
Quick Quiz created by: Emma Moulton
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