How do the principal quantum numbers of the quantum-mechanical model relate to the Bohr model of the atom?

These are all associated with particular physical properties. n, the principal quantum number, is associated with the total energy, the same way it is in the Bohr model, the orbital quantum number, is connected to the total angular momentum of the electron.

Explanation:

1. 1 mole of anything contains 6.022x10^23 pieces  

d  

2. a  

3. c, number  

5. 1.24x10^24atoms / 6.022x10^23atoms/mole = 2moles h2 atoms  

6. fe2br3 mass = 2moles x mass fe + 3 moles x mass br  

molar mass = grams / number of moles = g/mole  

to find moles = g / molar mass  

to find mass = g = molar mass / moles

the answer is barium and copper bromide