2. A cube has a side of 5 cm. It has a mass of 250 grams. The density of the cube is which one of the following?
A) 50 g/cm and will float in water
B) 2.0 g/cm and will float in water
C) 50 g/cm and will sink in water
D) 2.0 g/cm and will sink in water
E) 0.5 g/cm and will float in water

Ionic compounds are made of ions, and yet the overall charge of an ionic compound is neutral. why?

Adeuteron, 21h, is the nucleus of a hydrogen isotope and consists of one proton and one neutron. the plasma of deuterons in a nuclear fusion reactor must be heated to about 3.02×108 k . what is the rms speed of the deuterons? express your answer using two significant figures.

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.