Curious Kids is a series for children of all ages. If you have a question you’d like an expert to answer, send it to ...

A compound is a substance that contains two or more elements close elementA pure substance that is made from only one type of atom. Elements are listed on the periodic table. Elements cannot be ...

There are three main types of rock: igneous rock, metamorphic rock, and sedimentary rock. Almost all fossils are preserved in sedimentary rock. Organisms that live in topographically low places (such ...