Advertisements
Advertisements
प्रश्न
Calculate the amount of work done in the
1) Oxidation of 1 mole HCl(g) at 200 °C according to reaction.
4HCl(g) + O2(g) → 2Cl2(g) + 2H2O(g)
2) Decomposition of one mole of NO at 300 °C for the reaction
2NO(g) → N2(g) + O2(g)
Advertisements
उत्तर
Given:
1) Oxidation of 1 mole HCl(g)
Temperature = T = 200 °C = 473 K
2) Decomposition of one mole of NO
Temperature = T = 300 °C = 573 K
To find: Work done
Formula: W = - ΔngRT
Calculation:
1) The given reaction is for 4 moles of HCl. For 1 mole of HCl, the reaction is given as follows:
HCl(g) + `1/4` O2(g) → `1/2` Cl2(g) + `1/2` H2O(g)
Now,
Δng = (moles of product gases) - (moles of reactant gases)
Δng = `(1/2 + 1/2) - (1 + 1/4) = - 0.25` mol
Hence,
W = - ΔngRT
= -(- 0.25 mol) × 8.314 J K-1 mol-1 × 473 K
= + 983 J
2) The given reaction is for 2 moles of NO. For 1 mole of NO, the reaction is given as follows:
NO(g) → `1/2` N2(g) + `1/2` O2(g)
Now,
Δng = (moles of product gases) - (moles of reactant gases)
Δng = = `(1/2 + 1/2) - 1 = 0` mol
Hence,
W = - ΔngRT
= - 0 mol × 8.314 J K-1 mol-1 × 573 K
= 0 kJ
No work is done (since W = 0).
∴ The work done is +983 J. The work is done on the system.
∴ The work done is 0 kJ. There is no work done.
APPEARS IN
संबंधित प्रश्न
Select the most appropriate option.
If the standard enthalpy of formation of methanol is –238.9 kJ mol–1 then entropy change of the surroundings will be _______.
Select the most appropriate option.
Bond enthalpies of H–H, Cl–Cl, and H–Cl bonds are 434 kJ mol–1, 242 kJ mol–1, and 431 kJ mol–1, respectively. Enthalpy of formation of HCl is _______.
Answer the following question.
When 6.0 g of O2 reacts with CIF as per
\[\ce{2ClF_{(g)} + O2_{(g)} -> Cl2O_{(g)} + OF2_{(g)}}\]
The enthalpy change is 38.55 kJ. What is the standard enthalpy of the reaction? (Δr H° = 205.6 kJ)
Calculate the standard enthalpy of formation of \[\ce{CH3OH_{(l)}}\] from the following data:
\[\ce{CH3OH_{(l)} + 3/2 O2_{(g)} -> CO2_{(g)} + 2H2O_{(l)} }\]; ΔrH° = − 726 kJ mol-1
\[\ce{C_{(graphite)} + O2_{(g)} -> CO2_{(g)}}\]; ΔcH° = −393 kJ mol−1
\[\ce{H2_{(g)} + 1/2 O_{(g)} -> H2O_{(l)}}\]; ΔfH° = −286 kJ mol−1
Calculate the work done and comment on whether work is done on or by the system for the decomposition of 2 moles of NH4NO3 at 100 °C
NH4NO3(s) → N2O(g) + 2H2O(g)
Write the mathematical relation between ΔH and ΔU during the formation of one mole of CO2 under standard conditions.
Write the expression showing the relation between enthalpy change and internal energy change for gaseous phase reaction.
An ideal gas expands from the volume of 1 × 10–3 m3 to 1 × 10–2 m3 at 300 K against a constant pressure at 1 × 105 Nm–2. The work done is
Define enthalpy of neutralization.
Enthalpy of neutralization is always a constant when a strong acid is neutralized by a strong base: account for the statement.
Derive the relation between ∆H and ∆U for an ideal gas. Explain each term involved in the equation.
Calculate the enthalpy change for the reaction \[\ce{Fe2O3 + 3CO -> 2Fe + 3CO2}\] from the following data.
\[\ce{2Fe + 3/2O2 -> Fe2O3}\]; ΔH = −741 kJ
\[\ce{C + 1/2O2 -> CO}\]; ΔH = −137 kJ
\[\ce{C + O2-> CO2}\]; ΔH = −394.5 kJ
The standard enthalpy of formation of ammonia is −46.0 kJ mol−1. The enthalpy change for the reaction:
\[\ce{2NH3_{(g)} -> 2N2_{(g)} + 3H2_{(g)}}\] is ____________.
What is standard N ≡ N bond enthalpy from following reaction,
\[\ce{N2_{(g)} + 3H2_{(g)} -> 2NH3_{(g)}; \Delta H^0 = - 83 kJ}\]
\[\ce{ΔH^0_{(H-H)}}\] = 435 kJ; \[\ce{ΔH^0_{(N-H)}}\] = 389 kJ
The difference between heats of reaction at constant pressure and at constanl volume for the reaction
\[\ce{2C6H6_{(l)} + 15O2_{(g)} -> 12CO2_{(g)} + 6H2O_{(l)}}\] at 25°C in kJ
When 6.0 g of O2 reacts with CIF as per \[\ce{2ClF_{(g)} + O2_{(g)} -> Cl2O_{(g)} + OF2_{(g)}}\] the enthalpy change is 38.55 kJ. The standard enthalpy of the reaction is ____________.
Identify the equation in which change in enthalpy is equal to change in internal energy.
When 4 g of iron is burnt to ferric oxide at constant pressure, 29.28 kJ of heat is evolved. What is the enthalpy of formation of ferric oxide?
(Atomic mass of Fe = 56)
The enthalpy change for two reactions are given by the equations
\[\ce{2Cr_{(s)} + 1.5 O2_{(g)} -> Cr2O3_{(s)}}\];
∆H1 = −1130 kJ ............(i)
\[\ce{C_{(s)} + 0.5 O2_{(g)} -> CO_{(g)}}\];
∆H2 = −110 kJ .........(ii)
What is the enthalpy change, in kJ, for the following reaction?
\[\ce{3C_{(s)} + Cr2O3_{(s)} -> 2Cr_{(s)} + 3CO_{(g)}}\]
Given the bond energies N ≡ N, H – H and N – H bonds are 945, 436 and 391 kJ/mol respectively. The enthalpy of the reaction;
\[\ce{N2_{(g)} + 3H2_{(g)} -> 2NH3_{(g)}}\]
Work done when 2 moles of an ideal gas is compressed from a volume of 5 m3 to 1 dm3 at 300 K, under a pressure of 100 kPa is ____________.
For the reaction, \[\ce{N_{2(g)} + 3H_{2(g)} -> 2NH_{3(g)}}\], ΔH is equal to ______.
In which of the following reactions, ΔH is not equal to ΔU?
Calculate work done in oxidation of 4 moles of SO2 at 25°C. (Given: R = 8.314 JK−1 mol−1 ).
Define enthalpy.
Calculate the standard entropy change of the surrounding if standard enthalpy of formation of methyl alcohol is –240 kJ mol-1.
\[\ce{C(s) + 2H2(g) → CH4(g)}\]; ΔH= –74.8 kJ mol−1. Which of the following diagrams gives an accurate representation of the above reaction?
The equilibrium concentrations of the species in the reaction \[ \mathrm{A} + \mathrm{B} \rightleftharpoons \mathrm{C} + \mathrm{D} \] are 2, 3, 10 and 6 mol L-1, respectively at 300 K. ΔGº for the reaction is (R = 2 cal/mol K)
