Principal shell shows the main energy level, in that there are some more energy levels. This is how the atomic structure is defined according to the Quantum Mechanical model of atom. So exactly why do subshells exist and all i don't know
Answer:
The first one
Explanation:
Elements are as simple as it gets
Chemical weathering is the weakening and subsequent disintegration of rock by chemical reactions.
Answer:
Mg+F2= Mgf2
Explanation:
F 2 is an oxidizing agent, Mg is a reducing agent. ; Pale-yellow to greenish gas with a pungent, irritating odor.