complete the complex dimensional analysis problem to determine the price of one atom of aluminum. A 20cm X 20cm square of aluminum has a mass of 1.50g. A box of aluminum costs $1.29 and the area of foil in the box is 2.32m^2.

The answer is c.  h+  and oh−  react to form water (h2o). i just took the test and i got it right. hope this !

Vander waals forces are inter molecular bonds that exist within molecules of the same substance. a water molecule is made up of oxygen and hydrogen atoms which share electrons between each other. the vander waals forces are forces that exist between multitude of different  molecules of water. dipole dipole forces is the type of vander waals force that exist in water. the oxygen atom which is more electronegative pulls the shared electron closer to itself thus generating a partial negative charge while the hydrogen acquire a partial positive charge. these two different charges causes attraction to occur in water molecules.