Nuclear reactions involve changes to an atoms what?

Describe the chemical reaction based on the chemical equation below. also, explain whether the equation is balanced.

Identify the electromagnets with poles that are reversed from the electromagnet shown above

Pegmatites are igneous rocks in which the individual minerals are very large. typically, the minerals are all light-colored quartz, feldspar and muscovite. if you were given a black and white photograph of a pegmatite in a quarry (where the rock has been blasted and broken), what physical properties could you use to identify those three minerals in this hypothetical photo? describe each mineral and the specific diagnostic properties. be specific.