a gas has an empirical formula C6H7O5. When put in a 50mL bulb at 120 degrees celcius and 120kPa (pressure) it's mass is determined: the mass is 10.37 times as much as C6H6O. What is the molecular formula of the gas (C6H7O5)?
To determine the molecular formula of the gas given its empirical formula (C6H7O5), we need to find the ratio between the empirical formula mass and the molecular formula mass. This can be accomplished by comparing the experimental mass of the gas to the calculated mass of the empirical formula.
1. Calculate the empirical formula mass:
Since the empirical formula of the gas is C6H7O5, we can determine its empirical formula mass by adding up the atomic masses of its constituent elements.
Empirical formula mass = 6(C) + 7(H) + 5(O)
Empirical formula mass = 6(12.01 g/mol) + 7(1.01 g/mol) + 5(16.00 g/mol)
2. Determine the mass of the gas:
According to the problem, the mass of the gas is 10.37 times that of C6H6O. Therefore, we can calculate the mass of C6H6O by dividing the mass of the gas by 10.37.
Mass of C6H6O = Mass of the gas / 10.37
3. Calculate the molecular formula mass of C6H6O:
The molecular formula mass represents the actual mass of C6H6O. By using the atomic masses of its constituent elements, we can calculate it as follows:
Molecular formula mass = 6(12.01 g/mol) + 6(1.01 g/mol) + 1(16.00 g/mol)
4. Determine the ratio between the molecular formula mass and the empirical formula mass:
Ratio = Molecular formula mass / Empirical formula mass
5. From the ratio obtained, we can determine the multiplier by which the empirical formula needs to be increased to obtain the molecular formula. Round the ratio to the nearest whole number.
Multiplier = Ratio (rounded to the nearest whole number)
6. Multiply the subscripts of the empirical formula by the multiplier:
New molecular formula = (C6H7O5) * Multiplier
By following these steps, you can obtain the molecular formula of the gas given its empirical formula (C6H7O5).