The mass number of this atom is_

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

The melting point of sulfur is 115 °c and its boiling point is 445 °c. what state would sulfur be in at 200 °c?

11) burning your hand when accidentally touching a hot plate is an example of which heat transfer? a. conduction b. convection c. radiation d. none of these