A wavelength of 555nm contains 4.58 mJ, how many photons in the laser

1) how many electrons are in each energy level of the following elements? a. he b. na c. na d. ne 2) how many valence electrons are percent in the following atoms? a. s b. mg c. be d. cl 3) which of the following elements are stable as atoms? a. he b. o c. cl d. ar if you are able to provide the work as to how you got the answers that would be greatly appreciated. : )

What were the success and failures that came to boyle’s excitements?

Adrop of acetone (nail polish remover) has a mass of 35 mg and a density of 0.788 g/cm3. what is its volume in cubic centimeters?