Biology / Unit 1 Bio 0113 short lesson, about 20 seconds
Atomic Structure
Captions available
The idea
An atom has a nucleus of protons and neutrons at its center, surrounded by electrons occupying the space around it.
In practice
A proton carries a positive charge, a neutron none, and an electron a negative charge equal and opposite to a proton's.
Where people slip
Nearly all of an atom's volume is empty space around the nucleus — mass is not spread evenly through it.
Your place on the trail
Every lesson rests on earlier ones and opens later ones. Tap any to jump.
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