### Chapter 1 Question 25

Posted:

**Tue Oct 17, 2017 1:24 am**Sodium vapor lamps, used for public lighting, emit yellow light of wavelength 589 nm. How much energy is emitted by

(a) an excited sodium atom when it generates a photon

(b) 5.00 mg of sodium atoms emitting light at this wavelength

(c) 1.00 mol of sodium atoms emitting light at this wavelength

So for question 25, I got the answer for part A, but in part B it gives 5.00 mg of sodium atoms. Would you find the number of atoms in 5.00 mg and then multiply it by your answer in part A to find the Joules of energy emitted?

(a) an excited sodium atom when it generates a photon

(b) 5.00 mg of sodium atoms emitting light at this wavelength

(c) 1.00 mol of sodium atoms emitting light at this wavelength

So for question 25, I got the answer for part A, but in part B it gives 5.00 mg of sodium atoms. Would you find the number of atoms in 5.00 mg and then multiply it by your answer in part A to find the Joules of energy emitted?