# Problem: Ammonia (NH3) boils at -33oC; at this temperature it has a density of 0.81 g/cm3. The enthalpy of formation of NH3(g) is -46.2 kJ/mol, and the enthalpy of vaporization of NH3(l) is 23.2 kJ/mol.Calculate the enthalpy change when 4 L of liquid NH3 is burned in air to give N2(g) and H2O(g).How does this compare with ΔH for the complete combustion of 1 L of liquid methanol, CH3OH(l)? For CH3OH(l), the density at 25 oC is 0.792 g/cm3, and ΔHf equals -239 { m kJ/mol}.

###### FREE Expert Solution

We are asked to compare with ΔH for the complete combustion of 1 L of liquid methanol.

Reaction: 4 NH3(l) + 3 O2(g) → 2 N2(g) + 6 H2O(g)

= -1530.12 kJ

Calculate for 4 L liquid NH3

= - 176,930.36 kJ

93% (299 ratings) ###### Problem Details

Ammonia (NH3) boils at -33oC; at this temperature it has a density of 0.81 g/cm3. The enthalpy of formation of NH3(g) is -46.2 kJ/mol, and the enthalpy of vaporization of NH3(l) is 23.2 kJ/mol.

Calculate the enthalpy change when 4 L of liquid NH3 is burned in air to give N2(g) and H2O(g).

How does this compare with ΔH for the complete combustion of 1 L of liquid methanol, CH3OH(l)? For CH3OH(l), the density at 25 oC is 0.792 g/cm3, and ΔHf equals -239 .

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