when 0.100mole H2S was put into a 10.0-L vessel and heated to 1132C, it gave an equilibrium maixture containing 0.0285 mol H2. @hat are the valuesw of Kc and Kp at this temperature?
What's the reaction? Is it
............H2S(g) ==> H2(g) + S(s)
initial...0.01M.......0....0
change......-x......2x.....x
eqil.....0.01-x....2x.....x
(Note: (H2S) = moles/L = 0.1/10 = 0.01 M
Kc = (H2)/(H2S)
(H2) = 0.0285/10 = 0.00285 = 2x
Kc = (0.00285)^2/(0.01-x)
Kp = KcRTdelta n
To determine the values of Kc and Kp at the given temperature, we need to use the balanced chemical equation for the reaction involving H2S.
The balanced chemical equation for the reaction is:
H2S(g) ⇌ 2H2(g) + S(g)
According to the given information, the initial amount of H2S is 0.100 moles, and the equilibrium mixture contains 0.0285 moles of H2. We can use these values to calculate the number of moles of H2S that have reacted.
moles of H2S reacted = (initial moles of H2S) - (moles of H2 in equilibrium mixture)
= 0.100 - 0.0285
= 0.0715 moles
Since the stoichiometry of the reaction is 1:2, the number of moles of S produced can be calculated as:
moles of S = 0.0715 moles of H2S x (1 mole S / 1 mole H2S)
= 0.0715 x 1
= 0.0715 moles
Now, we can consider the equilibrium concentrations of the species involved in the reaction. The concentration of H2 and S is given as moles divided by the volume of the vessel, which is 10.0 L.
[H2] = (moles of H2) / (volume of vessel)
= 0.0285 moles / 10.0 L
= 0.00285 M
[S] = (moles of S) / (volume of vessel)
= 0.0715 moles / 10.0 L
= 0.00715 M
The equilibrium constant Kc is defined as the ratio of the concentrations of the products to the concentrations of the reactants, each raised to the power of their respective stoichiometric coefficients.
Kc = ([H2]^2[S]) / ([H2S])
= (0.00285^2 x 0.00715) / (0.0715)
= 0.00000819 M^2
The equilibrium constant Kp is related to Kc through the equation:
Kp = Kc x (RT)^Δn
Where R is the ideal gas constant, T is the temperature in Kelvin, and Δn is the difference between the sum of the stoichiometric coefficients of the gaseous products and the sum of the stoichiometric coefficients of the gaseous reactants.
Since there are no gaseous reactants or products other than H2S, Δn = (2 + 1) - 1 = 2.
By substituting the appropriate values, we can calculate Kp. The value of R is 0.0821 L·atm/(mol·K), and the temperature T is 1132 °C, which can be converted to Kelvin as follows:
T(K) = 1132 °C + 273.15
= 1405.15 K
Kp = Kc x (RT)^Δn
= 0.00000819 M^2 x (0.0821 L·atm/(mol·K) x 1405.15 K)^2
= 0.00000819 x (0.1155779858)^2
= 0.00000819 x 0.013367195
= 1.0925 x 10^-7 atm^2
Therefore, at the given temperature, the values of Kc and Kp for the reaction are approximately 0.00000819 M^2 and 1.0925 x 10^-7 atm^2, respectively.