Given the equation representing a system at equilibrium:
n2(g) + 3h2(g)< ==> 2nh3(g) + energywhich changes occur when the temperature of this system is decreased?
(1) the concentration of h2(g) increases and the concentration of n2(g) increases.
(2) the concentration of h2(g) decreases and the concentration of n2(g) increases.
(3) the concentration of h2(g) decreases and the concentration of nh3(g) decreases.
(4) the concentration of h2(g) decreases and the concentration of nh3(g) increases.

N2(g) + 3H2(g)<==>2NH3(g) + energy, the changes that occur when the temperature of this system is decreased is that concentration of H2(g) decreases and the concentration of NH3(g) increases. The answer is number 4. The rest of the choices do not answer the question above.

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.

answer is: naturally occurring solid, inorganic compound or element is mineral.

minerals usually have crystalline form, that means than crystal constituents (atoms, molecules or ions) are arranged in a highly ordered microscopic structure, forming a crystal lattice that extends in all directions.

for example magnetite is a mineral of iron oxide (fe₂o₃).

calcite is a carbonate mineral and the most stable polymorph of calcium carbonate (caco₃).

dolomite is an   carbonate mineral composed of calcium magnesium carbonate (camg(co₃)₂).