In short, an acid is a compound that can give up a hydrogen ion (a proton, H+) in solution. A base is a compound that can accept a proton. If you're looking at chemical equations, the acid will be the compound with more hydrogen atoms.Usually, an acid is positively charged.n short, an acid is a compound that can give up a hydrogen ion (a proton, H+) in solution. A base is a compound that can accept a proton. If you're looking at chemical equations, the acid will be the compound with more hydrogen atoms.
The lithosphere is the brittle outer layer of the solid Earth. The plates of plate tectonics are segments of the lithosphere. Its top is easy to see -- it's at the Earth's surface -- but the base of the lithosphere is in a transition, which is an active area of research.
Oceanic lithosphere is typically about 50-100 km thick (but beneath the mid-ocean ridges is no thicker than the crust). Continental lithosphere is thicker (about 150 km). It consists of about 50 km of crust and 100 km or more of uppermost mantle. Oceanic lithosphere consists mainly of mafic crust and ultramafic mantle and is denser than continental lithosphere, for which the mantle is associated with crust made of felsic rocks. The crust is distinguished from the upper mantle by the change in chemical composition that takes place at the Moho discontinuity.