Question

Consider the reaction: 2AB2 → A2 + 2B2 You start with one mole of AB2 and the reaction is done at constant pressure of 3.7 atm and 28.2 °C. Assume all gases behave like ideal gases. What is the value of the work (in J)?

Answer 1

-2503.2J

Step-by-step explanation:

At constant pressure, change in work follows the equation:

W = -P*ΔV

Where W is work, P is pressure (3.7atm) and ΔV is change in volume

We can obtain change in volume using ideal gas low:

ΔV = ΔnRT/P

Where Δn is change in moles (3moles of products - 2 moles of reactants = 1)

R is gas constant (0.082atmL/molK)

T is absolute temperature (28.2°C + 273.15 = 301.35K)

P is pressure (3.7atm)

ΔV = ΔnRT/P

ΔV = 1mol*0.082atmL/molK*301.35K/3.7atm

ΔV = 6.69L

And work is:

W = -3.7atm*6.69L

W = -24.71atmL

1atmL = 101.3J

-24.71atmL * (101.3J / 1atmL) =

-2503.2J