Which of the following statements about the arrangement of atoms, covalent bonds, and valence electrons in resonance structures is correct? A) Resonance structures have different arrangements of atoms and different arrangements of electrons.  
B) Resonance structures have different arrangements of atoms and the same arrangements of electrons.  
C) Resonance structures have the same arrangements of atoms as well as the same arrangements of electrons.  
D) Resonance structures have the same arrangements of atoms and different arrangements of electrons.

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.

well in order to answer this question you have to provide more information < 3

the answer is b. dilution