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the standard enthalpy of formation of urea, CO(NH2)2(6). The standard enthalpy of the reaction: CO(NH2)2() + H2Om) -› COz) + 2 NHare) is -133.42 kJ/mol. Calculate
Standard enthalpy of formation=-362kJ/mol
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Complete combustion of a 0.70-mol sample of a hydrocarbon, CxHy, gives 4.20 mol of CO2 and 3.50 mol of H20. The molecular formula of the original hydrocarbon is
0.7 CxHy + xO2 =4.2CO2 + 3.5H2O /0.7 CxHy + x/0.7O2 =6CO2 + 5H2O C6H10
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Define standard enthalpy of formation of a reaction. Write the reaction for the standard enthalpy of formation of C6H12O6
The standard enthalpy of formation is the change in enthalpy that accompanies the formation of one mole of the compound from its elements. The standard enthalpy of reaction occurs in a...
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the vapour pressure of h20 at 20degrees Celsius is 17mmhg.calculate the vapour pressure of solution of 3g of urea in 50g of water
To solve this we can use Raoult's law: p = p'x x = x(H2O) = 50/18 = 2.78 moles; moles of urea(CH4N2O) = 3/60 = 0.05 moles; mole fraction of...
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Justify - H*(CO2) = Delta_f H*(CO2) [*means zero in superscript and _f means f in subscript]
where, H* is standard enthalpy and Delta_f H* means standard enthalpy change of formation.
C + O2 --gt; CO2 Delta_f H*(CO2) = H*(CO2) - [H*(C) + H*(O2)] The standard enthalpy of elementary substance is zero: H*(C) = H*(O2) = 0 Therefore Delta_f H*(CO2) =...
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the standard enthalpy of combustion of ethane, carbon, and hydrogen are -1559.7 kJ/mol, -393kJ/mol and -286kJ/mol respectively.
Use Hess'ss law to find the enthalpy of formation of ethane
ΔHform(C2H6)=ΔHcomb(C2H6)-(2ΔHcomb(C)+3ΔHcomb(H2))=-1559.7-(2(-393)+3(-286))=84,3 kJ/mol
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Define enthalpy of combustion. Calculate the enthalpy of combustion of methanol if the enthalpies of formation of CO2,H20 andCH3OH are respectively .
-393.5kj/mol,-285.8kj/mol and -239.0kj/mol.
Answer: Enthalpy of combustion is the heat released during combustion of one mol amount of any substance by oxygen.You can calculate the combustion enthalpy of methanol using the enthalpy...
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Use the data to find another value for the enthalpy of buta-l , 3 —diene.
Bond energies Enthalpies of atomisation
C-H 413 KJ/mol C 715 KJ/mol
346 KJ/mol H 218 KJ/mol
610 KJ/mol
∆Hf = {Σ ∆H to turn elements into gaseous atoms -Σ ∆H to turn compound into gaseous atoms}4C(s) + 3H2(g) =CH2CHCHCH2(g)∆ Hf = {4x∆Hat [C] + 3 x E[H-H]) –...
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Calculate the enthalpy of combustion of ethyne (C2H2) from the data below: ΔHf (CO2) = -393kJ/mol , ΔHf (H2O) = -286kJ/mol and ΔHf (C2H2) = -229kJ/mol *
Solution:The standard enthalpy of combustion is ΔH∘c. It is the heat evolved when 1 mol of a substance burns completely in oxygen at standard conditions.The balanced chemical equation of combustion of...
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What mass of melamine, C3N3(NH2)3, will be obtained from 146.0 kg of urea, CO(NH2)2, if the yield of the overall reaction is 73.0 % ?
6(NH2)2CO = C3H6N6 +3CO2 + 6NH3 M((NH2)CO) = 60g/mol M (C3H6N6) = 126g/mol 360g (NH2)2CO - 126g C3H6N6 146Kg (NH2)2CO - xKg C3H6N6 x = 146*126/360 = 51.1 Kg C3H6N6...
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