The First-Order Decomposition of SO₂Cl₂ to Sulfur Dioxide Gas and Chlorine

The first-order decomposition of SO₂Cl₂ to sulfur dioxide gas and chlorine gas at 320°C has a half-life of 8.75 hr. If one begins with 600.mmHg of pure SO₂Cl₂ in a 5.00-L flask at 320°C, how long does it take for the total pressure in the flask to rise to 1.000 atm?

A) 6.45 hr
B) 11.1 hr
C) 3.91 hr
D) 20.3 hr
E) 6.91 hr