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.
Plates include both oceanic crust and continental crust. Stable subduction zones involve the oceanic lithosphere of one plate sliding beneath the continental or oceanic lithosphere of another plate due to the higher density of the oceanic lithosphere. That is, the subducted lithosphere is always oceanic while the over-riding lithosphere may or may not be oceanic.