Why is topsoil darker than the other levels of soil?

Give the orbital configuration of the phosphorus (p) atom.

How could a student test the effect of removing heat from a gas that is stored in a sealed container? what must occur in order for matter to change states?

3.09 lab: reaction of metals 1 which combinations of substances resulted in a chemical change? for each metal that participated in a chemical change, write the type of metal it is, based on your examination of the periodic table. were there any metallic compounds that did not react with either the acid or the base? write the type of metal, based on your examination of the periodic table. make a general statement about the reactivity of the metals in this experiment.