What is the difference between an orbital and a sublevel

Here's what I get  

Explanation:

An orbital is a region in space where an orbital is most likely to be found. It has a specific size, shape, and energy level, depending on its set of quantum numbers.

For example, the order of increasing orbital energies is n = 1, 2, 3, …. Orbitals with the same principal quantum number (n) belong to the same energy level.  

Orbitals in energy levels with n > 1 can be divided into groups depending on their secondary quantum number (l).

For example, the n=3 energy level consists of 10 orbitals —  one s, three p, and five d orbitals. the s, p, and d orbitals constitute three sublevels with slightly different energies in the n = 3 energy level.

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.