10. Cyclopropane is an anesthetic that is 85.6% carbon and 14.37% hydrogen by mass. What is the molecular formula of the compound if 0.45 L of cyclopropane reacts with excess oxygen at 120. °C and 0.72 atm to form a 1.35L of carbon dioxide and 1.35 L of water vapor?

To determine the molecular formula of cyclopropane, we need to follow a step-by-step process.

Step 1: Calculate the number of moles of carbon and hydrogen in the given mass percentages.
- Assume we have 100g of cyclopropane.
- From the given percentages, we can calculate the masses of carbon and hydrogen:
Mass of carbon = 85.6% of 100g = 85.6g
Mass of hydrogen = 14.37% of 100g = 14.37g
- Next, we need to convert the masses to moles using the molar mass of each element:
The molar mass of carbon is 12.01 g/mol, so the number of moles of carbon = 85.6 g / 12.01 g/mol = 7.13 mol
The molar mass of hydrogen is 1.01 g/mol, so the number of moles of hydrogen = 14.37 g / 1.01 g/mol = 14.23 mol

Step 2: Find the empirical formula of cyclopropane.
- The empirical formula represents the simplest whole number ratio of atoms in a compound.
- Calculate the mole ratio between carbon and hydrogen by dividing each value by the smallest value (7.13 mol):
Carbon: 7.13 mol / 7.13 mol = 1
Hydrogen: 14.23 mol / 7.13 mol = 2
- Therefore, the empirical formula of cyclopropane is CH2.

Step 3: Determine the molecular formula of cyclopropane.
- The molecular formula represents the actual number of atoms in a molecule.
- To find the molecular formula, we need to know the molar mass of cyclopropane.
- The molar mass of cyclopropane can be calculated by multiplying the empirical formula mass (CH2) by a whole number (n):
Empirical formula mass = 12.01 g/mol (C) + 2 * 1.01 g/mol (H) = 14.03 g/mol
- Given the molar mass of cyclopropane, we divide the molar mass of cyclopropane by the empirical formula mass to get the value of n:
Molar mass of cyclopropane (given in the problem) = 14.03 g/mol * n
For example, if the molar mass of cyclopropane is 42.09 g/mol, then n equals 3.
- Finally, we can write the molecular formula of cyclopropane by multiplying the empirical formula (CH2) by n:
Molecular formula of cyclopropane = CH2 * n

However, you did not provide the molar mass of cyclopropane in the question. Without that information, we cannot determine the exact molecular formula.