Answer:
The volume of the oxygen gas is 0.246 L
Explanation:
Step 1: Data given
Temperature = 39 °C = 312 K
Temperature = 725 torr = 725 / 760 atm = 0.953947 atm
Mass of mercuric oxide = 3.97 grams
Molar mass of mercuric oxide = 216.59 g/mol
Step 2: The balanced equation
2HgO → 2Hg + O2
Step 3: Calculate moles mercuric oxide
Moles = mass / molar mass
Moles HgO = 3.97 grams / 216.59 g/mol
Moles HgO = 0.0183 moles
Step 3: Calculate moles oxyen
For 2 moles HgO we'll have 2 moles Hg and 1 mol O2
For 0.0183 moles HgO we'll have 0.0183/2 = 0.00915 moles O2
Step 4: Calculate volume O2
p*V = n*R*T
⇒with p = the pressure of the gas = 0.953947 atm
⇒with V = the volume of O2 gas = TO BE DETERMINED
⇒with n = the moles of O2 = 0.00915 moles
⇒with R = the gas constant = 0.08206 L*atm/mol*K
⇒with T = the temperature = 312 K
V = (n*R*T)/p
V = (0.00915 moles * 0.08206 L*atm/mol*K * 312 K ) / 0.953947 atm
V = 0.246 L
The volume of the oxygen gas is 0.246 L
