The proton also has a spin quantum number, just like the electron. In an H atom, if the spins of the p⁺ and e^- are in the same direction, they are referred to as parallel. If they are in opposite directions, they are referred to as antiparallel. Suppose an H atom with its two particles having parallel spins is labeled H_p, and one with antiparallel spins is labeled H_a. Experiment shows that H_p is more stable than H_a. The energy between the two states has the same energy as a light wave with a wavelength of 21.0 cm.

(a) What is the difference in energy between the two states (in J)?

(b) What is the difference in energy between the two states (in J/mol)?

(c) The energy change of the reaction

is 435.996 kJ/mol. What are the energy changes (in kJ/mol) of the following two reactions?

(d) Under the right conditions, the metal sodium can make an ionic compound with hydrogen, with the resulting formula NaH. What is the proper name of this compound?

(e) What is the oxidation number of H_a? H_p? Na and H in NaH?

(f) Are there two possible compounds NaH_a and NaH_p? Why or why not?

(g) Given that hydrogen is the most common element in the universe, explain why radioastronomers detect virtually no emissions from the sky of radiation that has the wavelength 21.0 cm.

Transcribed Image Text:

H₂ → Hp + Hp