Question

The equilibrium constant for the following reaction:
Ca(HCO3)2(s) <--> CaO(s) + 2 CO2(g) + H2O(g)
would be:
Group of answer choices

A. K = [Ca(HCO3)2] / [CaO][CO2]2[H2O]

B. K = [CaO][CO2]2[H2O] / [Ca(HCO3)2]

C. K = [CO2]2[H2O]

D. K = [CO2]2[H2O] / [Ca(HCO3)2]

Answer 1

Answer:

C.) $K = {[CO_{2} ]^{2} [H_2O] }$

Explanation:

The general equilibrium expression looks like this:

$K = \frac{[B]^b[C]^{c} [D]^{d} }{[A]^{a}} }$

In this expression,

-----> K = equilibrium constant

-----> uppercase letters = formulas

-----> lowercase letters = balanced equation coefficients

Solids are not included in the expression, so Ca(HCO₃)₂(s) and CaO(s) should be left out. The products should be in the numerator and the reactants are in the denominator. This makes the expression:

$K = \frac{[B]^b[C]^{c} [D]^{d} }{[A]^{a}} }$                                  <----- Equilibrium expression

$K = {[CO_{2} ]^{c} [H_2O]^{d} }$                             <----- Insert gaseous formulas

$K = {[CO_{2} ]^{2} [H_2O] }$                               <----- Insert coefficients