Quinine in a 1.553-g antimalarial tablet was dissolved in sufficient 0.10 m hcl to give 250 ml of solution. a 10.00-ml aliquot was then diluted with 50.00 ml with the acid. the fluorescence intensity for the diluted sample at 347.5 nm provided a reading of 196 on an arbitrary scale. a standard 100-ppm quinine solution registered 125 when measured under conditions identical to those for the diluted sample. calculate the mass in milligrams of quinine in the tablet.

Your question is not clear but if you can explain yourself i would be glad to .  just trying to : ))

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.