When an electron moves from a higher energy level in an atom to a lower energy level, a. a redshifted spectrum is emitted. b. a photon is absorbed. c. a photon is emitted. d. a continuous spectrum is emitted.

C

Explanation:

The question asks to know what happens when an electron moves from a higher energy level to a lower energy level.

Firstly, it is important to note that when an electron moves from a lower energy level to a higher energy level, energy is absorbed by the atom. Conversely, when an electron moves from a region of higher energy to a region of lower energy, energy is released by the atom.

Thus we can say that the movement of an electron from a region of higher energy to a region of lower energy can result in the emission of a photon of light as energy is released by the atom

n2(g) + 3h2-> 2nh3(g)   this is the balanced equation

note the mole ratio between n2, h2 and nh3.   it is 1 : 3 : 2   this will be important.

moles n2 present = 28.0 g n2 x 1 mole n2/28 g = 1 mole n2 present

moles h2 present = 25.0 g h2 x 1 mole h2/2 g = 12.5 moles h2 present

based on mole ratio, n2 is limiting in this situation because there is more than enough h2 but not enough n2.

moles nh3 that can be produced = 1 mole n2 x 2 moles nh3/mole n2 = 2 moles nh3 can be produced

grams of nh3 that can be produced = 2 moles nh3 x 17 g/mole = 34 grams of nh3 can be produced

note:   the key to this problem is recognizing that n2 is limiting, and therefore limits how much nh3 can be produced.

just did the assignment and the answer was #1 +2 n