The equilibrium constant, K c , is calculated using molar concentrations. For ga

Question

The equilibrium constant, Kc, is calculated using molar concentrations. For gaseous reactions another form of the equilibrium constant, Kp, is calculated from partial pressures instead of concentrations. These two equilibrium constants are related by the equation

Kp=Kc(RT)n

where R=0.08314 L bar mol1 K1, T is the absolute temperature, and n is the difference in stoichiometric coefficients between gaseous products and gaseous reactants. For example, consider the reaction

N2(g)+3H2(g)2NH3(g)

for which n=2(1+3)=2.

Part A

For the reaction

3A(g)+2B(g)C(g)

Kc=87.2 L4 mol4 at a temperature of 285 C .

Calculate the value of Kp.

Part B

For the reaction

X(g)+4Y(g)3Z(g)

Kp=3.30×102 bar2 at a temperature of 375 C .

Calculate the value of Kc.

Explanation / Answer

Kp=Kc(RT)n

part A

3A(g)+2B(g)C(g)

Dn = 1-5 = -4

kp = 87.2*(0.08314*558.15)^-4 = 1.88*10^-5

part B

X(g)+4Y(g)3Z(g)

Dn = 3-5 = -2

3.3*10^-2 = x*(0.08314*648.15)^-2

x = Kc = 95.82

Related Questions

Navigate

• Browse (All)
• Browse T
• Subjects

Integrity-first tutoring: explanations and feedback only — we do not complete graded work. Learn more.