a scientist observed a number of different molecular changes of matter. which of the following observations provides evidence of a physical change

Which is true of chemicals? a. things containing chemicals always cost a lot of money. b. chemicals are never dangerous. c. chemicals are in many substances in a home. d. chemicals are rarely found on earth.

What is the number of moles of chemical units represented by 9.03x10^24? and how do i show work? (dumb it down )

Will give ! what are the advantages and disadvantages of nuclear power? check all that apply. one advantage of nuclear energy is that it does not produce carbon dioxide emissions. storage of nuclear waste is a short-term problem associated with nuclear energy. the problem with uranium mining is that a large quantity of uranium must be extracted to meet energy needs because the energy release from uranium fission is so low. safe operation of a nuclear power plant can be jeopardized by a human mistake.