The identities of substances are the same before and after which type of change

Three alkali metals in group 1 are a. calcium, strontium, barium b. boron, aluminum, gallium c. sodium, potassium, rubidium d. fluorine, iodine, chlorine

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.

How many absorptions would you expect to observe in the 13c nmr spectra of the following molecules? a) 3-chloropentane b) cis-4-methyl-2-pentene