Raschig reaction produces the industrially important reducing agent hydrazine N_

Question

Raschig reaction produces the industrially important reducing agent hydrazine N_2H_4 from NH_3 and OCl^-basic aqueous solution. The proposed mechanism is: NH_3 + OCl^- rightarrow NH_2Cl + OH^- fast NH_2Cl + NH_3 rightarrow N_2H_5 + Cl^- slow N_2 H_5^+ + OH^- rightarrow N_2 H_4 + H_2O fast (a) write the net overall reaction in the space provided. (b) Which step is the rate determining step? _____________________ (c) Indicate two intermediates involved in the overall reaction. ___________________ Consider the reaction 4PH_2(g) rightarrow P_ (g) + 6H_2(g). Suppose that, at a particular moment during the reaction, molecular hydrogen is being formed at rate of 0.431 M/s. At What rate is PH_3 changing? At a certain temperature, the following reactions have the equilibrium constants shown. S(s) + O_2(g) rightwardsharpoonoverleftwardsharpoon SO_2(g) K_c1 = 4.2 times 10^52 2S(s) + 3O_2(g) rightwardsharpoonoverleftwardsharpoon 2SO_2(g) K_c2 = 9.8 times 10^128 calculate the equilibrium constant, K_c following reaction at that temperature. 2SO_2(g) + O_2(g) rightwardsharpoonoverleftwardsharpoon 2SO_2(g) law for the reaction NH^+_4 (aq) 6 NO^- _2(aq) rightarrow N_2(g) + 2H_2O(l) is given by rate = [NH^+ _4][NO_^- _2], temperature the rate constant is 4.10 times 10^-4 M.s. Calculate the rate of the reaction at that [NH_4] = M and [NO^-_2] = 0.580 M.

Explanation / Answer

(2)

(a) Overall reaction is, add the three equations,

2 NH3 + OCl- ----------------> N2H4 + H2O + Cl-

(b) The slow step is called rate determining step.

So, step (2) is rate determining step.

(c) NH2Cl, N2H5+ and OH- are intermediates

(3)

Rate = - (1/4) d[PH3]/dt = + d[P4]/dt = + (1/6)d[H2]/dt

Now, (1/4) d[PH3]/dt = (1/6)d[H2]/dt

d[PH3]/dt = 4(1/6) (0.431)

d[PH3]/dt = 0.287 M/s

Related Questions

Navigate

• Browse (All)
• Browse R
• Subjects

---

---

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