HOF-->HF + 1/2O2(oxygen)
Half life: 30 minutes
If the partial pressure of HOF in a 1.00 L flask is initially 100 mm Hg at 25C, what is the total pressure in the flask and the partial pressure of HOF after exactly 30 minutes?
Half of it is gone.
So at t=0, pressure was 100
so at t=30, partial pressure is 50mmHg, total pressure is 5/2 of 50mmHg.
That is the amount of HOF converted to HF and 1/2 O2, added to the remaining 50mmHg.
I would approach the problem by setting up an ICE chart. In exactly 30 minutes, 1/2 of the HOF will remain, 1/2 will have formed HF and 1/2 of the HF will be O2. Total pressure = sum of partial pressures.
To determine the total pressure in the flask, we need to consider the partial pressure of HOF and the partial pressure of oxygen (1/2 O2) present in the flask.
Given:
Partial pressure of HOF (HOF): 100 mm Hg
Partial pressure of oxygen (1/2 O2): ?
Since HOF decomposes to HF and 1/2 O2, the partial pressure of oxygen is half of the initial partial pressure of HOF.
Partial pressure of oxygen (1/2 O2) = 1/2 * partial pressure of HOF = 1/2 * 100 mm Hg = 50 mm Hg
Therefore, after exactly 30 minutes, the partial pressure of oxygen (1/2 O2) in the flask would be 50 mm Hg.
Now, to determine the total pressure in the flask, we need to consider the sum of the partial pressures of HOF and oxygen.
Total pressure = Partial pressure of HOF + Partial pressure of oxygen
Total pressure = 100 mm Hg + 50 mm Hg = 150 mm Hg
Therefore, after exactly 30 minutes, the total pressure in the flask would be 150 mm Hg and the partial pressure of HOF would be 100 mm Hg while the partial pressure of oxygen (1/2 O2) would be 50 mm Hg.