Electrons are negatively charged particles. They are attracted to the positively charged particles in the center, or nucleus, of an atom.
The word magma refers to molten rock deep inside Earth. That rock is called lava when it reaches Earth’s surface.
Humans are changing the world in profound ways. Some scientists think those changes have launched a new epoch in Earth’s history: the Anthropocene.
The tonsils are pads of tissue in the throat that are part of the body’s immune system.
Haptic is an adjective used to describe things related to our sense of touch.
In physics, plasma refers to one of the four states of matter. In medicine, plasma describes the part of blood that ferries cells, nutrients and more throughout the body.
Aerosols are tiny bits of solids or drops of liquids suspended in gas. Aerosols include mist, fog and soot, as well as pollution from fossil fuels.
Oxidation and reduction are two parts of a chemical process in which one atom steals electrons from another.
Mass shows how much an object resists speeding up or slowing down when force is applied — a measure of how much matter is in it.
Nicotine is an addictive substance found in tobacco plants. It's what makes it so difficult to quit smoking or vaping.
In chemistry, this attachment between atoms forms because of the power of attraction. Chemical bonds make up every solid object on Earth.
Pollen is a mass of tiny reproductive cells. These grains combine with egg cells to form seeds — but on the way, they can make some people miserable.