A mortar and pestle are a pair of tools used by chemists and pharmacists (among others) to grind substances into small pieces. The mortar is the bowl and the pestle is the crushing stick.

Carbon is a part of every macromolecule (proteins, lipids, nucleic acids, and carbohydrates) that make up our bodies. There wouldn't be much of a human body to speak of without it.

A crucible is used in chemistry to heat things, such as reaction mixtures. They are typically made out of ceramics and are thus resistant to quite a bit of heat.

Only plants (and some photosynthetic microorganisms, but they aren't nearly as significant) can introduce energy into the Earth's biosphere. They are eaten by animals, and this energy circulates throughout the food chain.

De facto (no terminal r) means that something is established by practice or common acceptance. For example, a country may have an official language (such as English, as a remnant of colonialism), but the de facto official language is Spanish (or whatever). De jure means that something is established by actual law (hence the jure). … Read more