An unknown organic compound gives the following CHN data: 54.53% carbon, 9.15% hydrogen, no measurable nitrogen content. What is the empirical formula for this compound

The air is going to come out because of the low pressure.

The net force is 100

They make up examples of physical properties 

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.