Which of the following best characterizes the field of chemistry, a) scientific study of the laws of nature and the origin of all the things around us b) scientific study of matter and how materials interact with each other at the atomic level c) scientific study of how celestial objects move?

What is the energy of a photon of ultraviolet radiation with a frequency of 4.4 × 1015 hz? planck’s constant is 6.63 × 10–34

How will the system respond to a temperature increase?

22. the top of a cliff is located a distance h above the ground. at a distance h/2 there is a branch that juts out from the side of the cliff, and on this branch a bird's nest is located. two children throw stones at the nest with the same initial speed, one stone straight downward from the top of the cliff and the other stone straight upward from the ground. in the absence of air resistance, which stone hits the nest in the least amount of time?