PLEASE HELP The theory of plate tectonics is supported by evidence that crustal plates move relative to each other. How does this observation support the theory of plate tectonics?
It suggests that plates are dragged around by ocean currents.
It suggests that plates are dragged around by air currents.
It suggests that plates can move independently of one another.
It suggests that plates cannot move independently of one another.

non independantly

Explanation:

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.

metric time was an attempt to create a standard unit of time based off of 10, but it never took off an is not included in the metric system (si)