A mixture of 1.57 mol of N2, 1.92 mol of H2 and 8.13 mol of NH3 is introduced into a 20 L reaction vessel at 500 K. At this temperature, the equilibrium constant, Kc for the reaction N2 (g) + 3H2 (g) ↔ 2NH3 (g) is 1.7 × 102.
Is the reaction mixture at equilibrium? If not, what is the direction of the net reaction?
The given reaction is:
N2 (g) + 3H2 (g) ↔ 2NH3 (g)
The given concetration of various species is:
N2 = 1.57/20 molL-1
H2 = 1.92/20 molL-1
NH3 = 8.13/20 molL-1
Now, reaction quotient Qc is:
Qc = (8.13/20)2 / (1.57/20) (1.92/20)3
= 2.4 x 10-3
Since,Qc ≠ Kc the reaction mixture is not at equilibrium.
Again, Qc > Kc. Hence, the reaction will proceed in the reverse direction.
The mass of an electron is 9.1 × 10–31 kg. If its K.E. is 3.0 × 10–25 J, calculate its wavelength.
Calculate the amount of carbon dioxide that could be produced when
(i) 1 mole of carbon is burnt in air.
(ii) 1 mole of carbon is burnt in 16 g of dioxygen.
(iii) 2 moles of carbon are burnt in 16 g of dioxygen.
Calculate the wavelength of an electron moving with a velocity of 2.05 × 107 ms–1.
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(b) MnO4 – (aq) + SO2 (g) → Mn2+ (aq) + HSO4– (aq) (in acidic solution)
(c) H2O2 (aq) + Fe 2+ (aq) → Fe3+ (aq) + H2O (l) (in acidic solution)
(d) Cr2O7 2– + SO2(g) → Cr3+ (aq) + SO42– (aq) (in acidic solution)
In a process, 701 J of heat is absorbed by a system and 394 J ofwork is done by the system. What is the change in internal energy for the process?
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(i) 300 atoms of A + 200 molecules of B
(ii) 2 mol A + 3 mol B
(iii) 100 atoms of A + 100 molecules of B
(iv) 5 mol A + 2.5 mol B
(v) 2.5 mol A + 5 mol B
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(i) 1 g Au (s)
(ii) 1 g Na (s)
(iii) 1 g Li (s)
(iv) 1 g of Cl2(g)
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(a) inert pair effect
(b) allotropy and
(c) catenation?
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(ii) whose value is independent of path
(iii) used to determine pressure volume work
(iv) whose value depends on temperature only.
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H2O(s) + F2(g) → HF(g) + HOF(g)
Justify that this reaction is a redox reaction.