Question

Consider the reaction H2CO(g)+ O2(g)Co2g)+H2o0) Using standard thermodynamic data at 298K, calculate the entropy change for the surroundings when 1.61 moles of H2CO(g) react at standard conditions AS surroundings J/K Consider the reaction N2(g) +202(g2No2(g) Using standard thermodynamic data at 298K, calculate the entropy change for the surroundings when 1.95 moles of N2(g) react at standard conditions. AS surroundings J/K

Answer 1

Equation: H2CO() O2(g)> CO2(g) Standard enthalpy change of the reacti on is H20() f(reactarts) f(CH) f (o2) - (1-393.51) +1-285.83 1x-109.15)+(1x0) kJ/mol -570.19 kJ/mol AS 1.913 kJ/K aurondng- T" 298 K 1913 J/K For1.61 moles of H2CO, ASmomditgs1 = 1.61mol H2COx 1 mol H2CO +3080 J/K Equation N2 (g) +202(8)> 2NO2 (g) Standard enthalpy change ofthe reaction, ΔΗ0n-mAHo (products)-zAHo (reactants) kJ/m ol kJ lmolxo kJ mol 2 molx 33.18 kJ mol mol = 66.36 kJ 6636 k0.2227 kJ/K 298 K AS T" 222.7 J/K 1 mol N2 For2.27 moles of Fe203, S arrondig = 1.95 mol Na 434.3 J/K