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.
The enthalpy of formation for all elements in their standard states is _______.
Obtain the relationship between ΔH and ΔU for gas phase reactions.
Calculate the work done in the decomposition of 132 g of \[\ce{NH4NO3}\] at 100°C.
\[\ce{NH4NO3_{(s)} -> N2O_{(g)} + 2H2O_{(g)}}\]
State whether work is done on or by the system.
Answer the following question.
Calculate standard enthalpy of reaction,
Fe2O3(s) + 3CO(g) → 2Fe(s) + 3CO2(g), from the following data.
Δf H°(Fe2O3) = - 824 kJ/mol,
Δf H°(CO) = - 110 kJ/mol,
Δf H°(CO2) = - 393 kJ/mol
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
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 combustion.
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 enthalpies of formation of SO2 and SO3 are −297 kJ mol−1 and −396 kJ mol−1 respectively. Calculate the standard enthalpy of reaction for the reaction: \[\ce{SO2 + 1/2O2 -> SO3}\]
For which of the following ∆U = ∆H?
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
Identify the equation in which change in enthalpy is equal to change in internal energy.
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?
\[\ce{3C_{(s)} + Cr2O3_{(s)} -> 2Cr_{(s)} + 3CO_{(g)}}\]
In which of the following reactions, ∆H is greater than ∆U?
For the reaction, \[\ce{A_{(s)} + 2B_{(g)} -> 5C_{(s)} + D_{(l)}}\], ∆H and ∆U are related as ____________.
What is the amount of work done when 0.5 mole of methane, CH4 (g), is subjected to combustion at 300 K? (Given, R = 8.314 JK-1mol-1)
The work done during combustion of 9 × 10-2 kg of ethane, C2H6 (g) at 300 K is ______.
(Given R = 8.314 J deg-1, atomic mass C = 12, H = 1)
Calculate the work done during the combustion of 0.138 kg of ethanol, C2H5OH(l) at 300 K.
Given: R = 8.314 Jk−1 mol−1, molar mass of ethanol = 46 g mol−1.
Under what conditions ΔH = ΔU?
Calculate the work done in oxidation of so2(g) at 25°C if, \[\ce{2SO_{2(g)} + O2_{(g)} -> 2SO_{3(g)}}\], R = 8.314 J K−1 mol−1.
Calculate ΔS of the surrounding if the standard enthalpy of formation of methanol is − 238.9 kJ mol−1.
Calculate work done in oxidation of 4 moles of SO2 at 25°C. (Given: R = 8.314 JK−1 mol−1 ).
