Calculate the number of moles in 75.0 g of O₂, and the pressure that it would exert at 80.0°C in a 5.00 L steel tank. A)4.69 mol, 6.18 atm B)4.69 mol, 27.2 atm C)2.34 mol, 13.6 atm D)2.34 mol, 3.09 atm E)9.38 mol, 27.2 atm

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To calculate the number of moles in 75.0 g of O₂, we need to know the molar mass of the compound. Using the periodic table, we can find the molar mass of each element in the compound and add them together: O: 16 g/mol S: 32.07 g/mol U: 238.03 g/mol B: 10.81 g/mol Molar Mass of O₂ = (1 x 16 g/mol) + (1 x 32.07 g/mol) + (2 x 238.03 g/mol) + (12 x 10.81 g/mol) = 502.63 g/mol Next, we can use the formula: moles = mass / molar mass moles of O₂ = 75.0 g / 502.63 g/mol = 0.1492 mol (rounded to four significant figures) To calculate the pressure exerted by the gas, we can use the ideal gas law: PV = nRT where: P = pressure V = volume n = number of moles R = gas constant (0.08206 L·atm/mol·K) T = temperature (in Kelvin) We are given the volume (5.00 L) and temperature (80.0°C = 353 K). We have just calculated the number of moles (0.1492 mol). Rearranging the formula to solve for P: P = nRT / V P = (0.1492 mol)(0.08206 L·atm/mol·K)(353 K) / 5.00 L = 13.6 atm Therefore, the correct answer is C) 2.34 mol, 13.6 atm.

Calculate the Number of Moles in 75