Final answer:
To calculate the molar mass of the unknown gas, use the ideal gas law equation. The molar mass can be calculated by dividing the mass by the number of moles. The density of the gas can be calculated by dividing the mass by the volume. The pressure of the gas can be calculated using the formula for pressure, and the final temperature can be calculated using the formula for temperature.
Step-by-step explanation:
To calculate the molar mass of the unknown gas, we can use the ideal gas law equation PV = nRT, where P is the pressure, V is the volume, n is the number of moles, R is the ideal gas constant, and T is the temperature. We need to calculate the number of moles of the unknown gas first:
n = PV / RT = (185.998 g - 185.375 g) / ((425 torr) * (0.550 L) / ((0.0821 L·atm/mol·K) * (25°C + 273.15))) ≈ 0.00804 mol of the unknown gas
To calculate the molar mass of the unknown gas, we can use the formula:
Molar Mass = mass / number of moles = (185.998 g - 185.375 g) / 0.00804 mol ≈ 77.4 g/mol
To calculate the density of the gas in g/L, we can use the formula:
Density = mass / volume = (185.998 g - 185.375 g) / 0.550 L ≈ 1.134 g/L
To calculate the pressure of the gas in the 455-mL flask, we can use the formula:
Pressure = (mass of gas / volume of gas) * (volume of new flask / volume of old flask) = (185.998 g - 185.375 g) / 0.550 L * (0.455 L / 0.550 L) ≈ 380.65 torr
To calculate the final temperature of the system if the pressure in the 455-mL flask is doubled, we can use the formula:
Final Temperature = Initial Temperature * (Final Pressure / Initial Pressure) = 25°C * (2 * 380.65 torr / 425 torr) ≈ 47.37°C