Question

Phosphorus is an eleneat commonly found in the infernal regions. It exists in various forms called allotropss. Cons-. De: the reaction at 1210 K (15 points): P4(g) doubleheadarrow 2 P2(g) In a 4.0 L container, at 1210 Kelvin. an equilibrium mixtrre is found to consist of p(P4) = 0.250 atm and P(P2) = 1.40atm. Determine the valie cf the equilibrium constant Kp, at this temperature. Kp = Suppose that aner nixmre of gases is produced also at 1210 K where: P(P4)=1.81 times 10^- atm and p(P2) = 0.119 atm. Calculate die reaction quotient. deternmine whether for these conditions, the reaction is sponaneous to the right (R); spointaneous to die left (L); or at equilibrium CE); calculate the value of Ke; and calculate the value of delta G Q = Reaction is: Kc = deltaGdegree = kJ,mol

Answer 1

Answer – there is given reaction –

P₄(g) <-----> 2 P₂(g)

a)At equilibrium , p(P₄) = 0.250 atm , p(P₂) = 1.40 atm

we know the Kp expression for this reaction

Kp = p(P₂)² / p(P₄)

     = (1.40)² / 0.250

    = 7.84

b) At initial p(P₄) = 1.81*10^-3 atm , p(P₂) = 0.119 atm

we know reaction quotient , Q = p(P₂)² / p(P₄)

                                                = (0.119)² / 1.81*10^-3

                                               = 7.82

So the Kp and Qp are the same, means reaction is at equilibrium (E)

We know

Kp = Kc*(RT)^∆n

7.84 = Kc * (0.0821*1210 K)¹

Kc = 7.84 / 0.0821*1210

       = 0.0789

We know,

∆G^o= -RTlnK

       = -8.314 J/mol.K *1210 K * ln 7.84

       = - 20715 J/mol

       = - 20.7 kJ/mol