Advertisements
Advertisements
प्रश्न
Write the expression showing the relation between enthalpy change and internal energy change for gaseous phase reaction.
Advertisements
उत्तर
∆H = ∆U + ∆ng RT
where ∆H is change in enthalpy,
∆U is a change in internal energy,
Δng is the difference between the number of moles of products and those of reactants.
APPEARS IN
संबंधित प्रश्न
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 in brief.
Obtain the expression for work done in chemical reaction.
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)
Write the mathematical relation between ΔH and ΔU during the formation of one mole of CO2 under standard conditions.
The work done by the liberated gas when 55.85 g of iron (molar mass 55.85 g mol–1) reacts with hydrochloric acid in an open beaker at 25°C
Define enthalpy of neutralization.
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 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: \[\ce{SO2 + 1/2O2 -> SO3}\]
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
For which of the following ∆U = ∆H?
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)
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?
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 ΔU if 2 kJ heat is released and 10 kJ of work is done on the system.
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 ).
\[\ce{C(s) + 2H2(g) → CH4(g)}\]; ΔH= –74.8 kJ mol−1. Which of the following diagrams gives an accurate representation of the above reaction?
