If 45.8 grams of mgo are dissolved in 205 grams of water, what is the concentration of the solution in percent by mass?

Which substances have the lowest melting points: ionic covalent, or metallic

What is the ph of a solution that has a hydrogen ion concentration of 1.0 * 10 -9 m?

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.