what element is located in the first row group 1? Why is the box for this element separate from the rest of the group 1 by a slight space?

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

1) a light bulb takes in 30 of energy per second. it transfers 3j as use energy. calculate the efficiency. second. it transfers 3j as useful light energy and 27j as heat energy. calculate the efficiency

Amethod of separation that employs a system with two phases of matter, a mobile phase and a stationary phase, is called