Answer:
atom is the smallest unit of ordinary matter that forms a chemical element. Every solid, liquid, gas, and plasma is composed of neutral or ionized atoms. Atoms are extremely small, typically around 100 picometers across.
<span>There are more than 550 active
volcanoes in the world, almost all of which are located at convergent
tectonic plate boundaries. This includes all of the volcanoes in the
Pacific Ring of Fire, such as Japan's Mount Fuji, as well as Mount Saint
Helens, Popocafepetl in Mexico and Azul in the Andes Range.</span>
A chemical formula identifies each constituent element by its chemical symbol and indicates the proportionate number of atoms of each element.
<em>For example, the empirical formula of ethanol may be written C2H6O because the molecules of ethanol all contain two carbon atoms, six hydrogen atoms, and one oxygen atom.</em>
