Answer:
The correct answer is 4.46 L.
Explanation:
Based on the given information, the mass of NiO given is 23.87 grams. The no. of moles can be determined by using the formula, n = weight/molecular mass. The molecular mass of NiO is 74.69 gram per mole. Now the moles of NiO will be,
Moles of NiO = 23.87 g/74.69 g/mol = 0.3196 moles
Now the moles of O2 will be = 1/2 * moles of NiO
= 1/2 * 0.3196 = 0.160 moles
The total pressure given in the question is 755 mmHg, and the vapor pressure mentioned is 55.4 mmHg. So, the pressure of O2 will be,
= Total pressure - Vapor pressure
= 755 mmHg - 55.4 mmHg
= 699.6 mmHg
= 699.6 * (1 atm / 760 mmHg)
= 0.9205 atm
Now the volume of the oxygen gas collected can be calculated by using the ideal gas law equation, that is, PV = nRT
0.9205 atm . V = 0.160 moles * 0.08206 L-atm/mol-K * 313 K (273 + 40 K)
V = 0.160 moles * 0.08206 L-atm/mol-K * 313 K / 0.9205 atm
V = 4.46 L
