Question

What's the expression for the equilibrium constant of 2NH3(g)+CO2(g)_N2CH4O(g)+H2O(g)

Answer 1

Explanation:

Equilibrium)is(a(condition(that(occurs(when(a(chemical(reaction(is(

reversible,(and(the(forward(and(reverse(reactions(occur(simultaneously,(at(the(same(

rate.

Chemical(reactions(can(be(classified(into(one(of(two(broad(categories:(those(

reactions(that(“go(to(completion”(and(those(reactions(that(establish(”equilibrium”.((

Burning methane(in(oxygen(to(form(carbon(dioxide(and(water(is(a(“goes(to(

completion”(reaction,(and(is(indicated(using(a(singleCheaded(reaction(arrow:

CH4 +(2O2 → CO2 +(2H2O

Equilibrium(reactions(do(not(go(to(completion;(instead,(the(two(reactions(

(arbitrarily(labeled(“forward”(and(“reverse”) occur(simultaneously.((The(forward(

and(reverse(reactions(are(opposite;(the(reverse(reaction(is(the(forward(reaction(

written(backwards.((For(example,(nitrogen(gas(and(hydrogen(gas(react(to(form(

ammonia:

N2(g)(+(3H2(g)(→ 2NH3(g)

This(reaction(requires(pressures(between(2100(and(3600(psi(and(temperatures(

between(300(and(550(oC.((At(these(pressures(and(temperatures(ammonia(

spontaneously(decomposes into(nitrogen(and(hydrogen(gas:

2NH3(g)(→ N2(g)(+(3H2(g)

Eventually,(these(two(reactions(occur(at(the(same(rate.((When(this(happens,(

the(concentrations(of(nitrogen,(hydrogen,(and(ammonia(become(constant,(and(the(

system(is said(to(be(“at(equilibrium”.((Typically,(we(represent(chemical(equilibrium(

using(a(doubleCheaded(reaction(arrow:

N2(g)(+(3H2(g)(⇔ 2NH3(g)

The(equilibrium)constant,(Keq,(is(the(ratio(of(the(product(concentration to(

the(reactant(concentration when(equilibrium(is(achieved.( The(exact(mathematical(

form(of(the(equilibrium(expression,(relating(Keq to(the(various(reactants(and(

products,(depends(on(the(specific(chemical(equilibrium(considered.((For(the

ammonia(system,(the(equilibrium(expression(is:

Keq = [NH3 ]

2

[N2 ][H2 ]