One of the emission spectral lines for be3+ has a wavelength of 253.4 nm for an electronic transition that begins in the state with n=5. what is the principal quantum number of the lower-energy state corresponding to this emission?

If a plot weight (in g) vs. volume (in ml) for a metal gave the equation y= 13.41x and r^2=0.9981 what is the density of the metal?

The table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 9 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of tthe table compares the number of electrons in two unknown neutral atoms. comparison of electrons atom number of electrons a 9 d 11 use this information to determine the number of valence electrons in the atoms. which of the following correctly compares the stability of the two atoms? both are unreactive. both are highly reactive. a is unreactive and d is reactive. a is reactive and d is unreactive.

What is the chemical formula for the compound formed between sodium and flour one