The main difference between speed and velocity involves
a. gravity.
b. weight.
c. direction.
d. distance.

Achlorine atom has 17 protons and 18 neutrons. what is its mass number? what is its atomic number?

Which component of the earth’s atmosphere is decreased due to photosynthesis?

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?