Calculate the change in enthalpy, ΔH in joules (J) for the reaction below carried out at constant pressure of 11.1 atm at a volume of -2.3 m3 with internal energy of -90.9 kJ.

N2 +3H2 → 2NH3 ΔH = ?

-64.4 x 103 J

-116.4 x 103 J

+116.43 J

+ 64.4 J

1 answer

The calculation involves using the equation:

ΔH = ΔE + PΔV

where ΔE is the change in internal energy, P is the constant pressure, and ΔV is the change in volume.

First, we need to convert the internal energy from kilojoules to joules:

ΔE = -90.9 kJ = -90.9 x 10^3 J

Next, we need to calculate the value of ΔV. The given volume of -2.3 m^3 suggests that there has been a decrease in volume, which means that ΔV is negative:

ΔV = -2.3 m^3

Now we can substitute these values into the equation and solve for ΔH:

ΔH = ΔE + PΔV
ΔH = -90.9 x 10^3 J + (11.1 atm)(-2.3 m^3)
ΔH = -90.9 x 10^3 J - 25.53 x 10^3 J
ΔH = -116.43 x 10^3 J

Therefore, the change in enthalpy for the given reaction at constant pressure is -116.4 x 10^3 J. The answer is B.