The First-Order Decomposition of Phosphene to Phosphorus and Hydrogen, Shown $\rarr$

question 112

Multiple Choice

The first-order decomposition of phosphene to phosphorus and hydrogen, shown below, 4PH₃(g) $\rarr$ P₄(g) + 6H₂(g)
Has a half-life of 35.0 s at 680°C.Starting with 520 mmHg of pure phosphene in an 8.00-L flask at 680°C, how long will it take for the total pressure in the flask to rise to 1.000 atm?

• A)628 s
• B)33.4 s
• C)51.2 s
• D)111 s
• E)48.3 s

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