Answer:
moles = 0.093 moles
Explanation:
In this case, we know that this reaction is taking plave in a vessel that has a 730 torr of total pressure.
The total pressure is a value obtained by:
Pt = Pwater + PO2
We need to know the pressure of O2, because then, with stoichiometry, we can calculate the moles of KClO3
The pressure of oxygen is:
PO2 = 730 - 26 = 704 Torr
Now, this pressure is in Torr, and we need to convert it to Atm, so:
704 Torr / 760 Torr = 0.9263 atm
Now, let's use the ideal gas equation:
PV = nRT
With this expression, we will calculate the moles of O2, and then, the moles of KClO3:
n = PV/RT
R = 0.082 L atm /K mol
P = 0.9263 atm
V = 3.72 L
T = 27 + 273 = 300 K
Replacing the data:
n = 0.9263 * 3.72 / 300 * 0.082
n = 0.14 moles
Finally, by stoichiometry, we know that 2 moles of KClO3 produces 3 moles of O2, so:
moles of KClO3 = 0.14 * 2/3 = 0.093 moles of KClO3