Explain how a star's absorption spectrum and the concept of red shift help support the Big Bang Theory.

Give one example to show that when substances are mixed, it may result in a chemical or a physical change depending on the conditions.

Which is an example of an exothermic process?

Materials will have different energies associated with the electrons inside them. this is related to how strongly bound they are by their work function. if we sandwich a material with a very low energy between two materials with a high energy, we create a trap for an electron. if this trap is very narrow in one direction in comparison to the others, this is approximately a 1-dimensional box that confines the electron. what is the lowest energy of an electron in the box if the thinnest direction across the materials is 4.81 nm?