Given a mixture of sand and water, state one process that can be used to separate water from the sand

In this chemical reaction, 325 grams of barium (ba) react completely. how many moles of lithium (li) are produced?

The bond energy for the van der waals bond between two helium atoms is 7.9×10−4ev. assuming that the average kinetic energy of a helium atom is (3/2)kbt, at what temperature is the average kinetic energy equal to the bond energy between two helium atoms

Amixture with the same composition throughout is!