Given the Empirical formula: C6H7N, and a molecular mass of 372.52 g/mol, How do I find the MOLECULAR formula for the compound?
The molecular formula can be found by dividing the molecular mass by the empirical formula mass.
Empirical formula mass = 6(12.01) + 7(1.008) = 77.09 g/mol
Molecular mass/Empirical formula mass = 372.52/77.09 = 4.83
Therefore, the molecular formula is C4H5N4.
To find the molecular formula for a compound given its empirical formula and molecular mass, you need to determine the ratio between the empirical formula's mass and the actual molecular mass.
Here's how you can do it:
1. Calculate the empirical formula mass:
- Determine the molar mass of each element in the empirical formula:
- Carbon (C): 12.01 g/mol
- Hydrogen (H): 1.01 g/mol
- Nitrogen (N): 14.01 g/mol
- Multiply the number of atoms of each element by their respective molar masses, then sum the results:
- Empirical formula mass = (6 * 12.01 g/mol) + (7 * 1.01 g/mol) + (1 * 14.01 g/mol)
2. Calculate the ratio between the empirical formula mass and the molecular mass:
- Ratio = Molecular mass / Empirical formula mass
3. Determine the integer factor that scales up the empirical formula to match the molecular formula:
- Divide the molecular mass by the empirical formula mass and round to the nearest whole number.
- This will give you the factor by which you need to multiply the empirical formula to obtain the molecular formula.
4. Multiply the subscripts of the empirical formula by the integer factor to obtain the molecular formula.
Let's calculate it for the given empirical formula C6H7N and molecular mass of 372.52 g/mol:
1. Empirical formula mass = (6*12.01 g/mol) + (7*1.01 g/mol) + (1*14.01 g/mol)
= 72.06 g/mol + 7.07 g/mol + 14.01 g/mol
2. Ratio = 372.52 g/mol / Empirical formula mass
3. Integer factor = Round the ratio to the nearest whole number.
4. Multiply the subscripts of the empirical formula by the integer factor to obtain the molecular formula.
By following these steps, you should be able to find the molecular formula for the compound.
To find the molecular formula from the empirical formula and the molecular mass, you need to determine the ratio between the empirical formula mass and the molecular mass. Here are the steps to find the molecular formula:
Step 1: Calculate the empirical formula mass.
The empirical formula mass represents the sum of the atomic masses of the atoms in the empirical formula of the compound. To calculate the empirical formula mass, you need to determine the atomic masses of carbon (C), hydrogen (H), and nitrogen (N) from the periodic table.
C: 12.01 g/mol
H: 1.01 g/mol
N: 14.01 g/mol
Now, multiply the atomic masses by the subscripts in the empirical formula and add them together:
C6H7N:
(6 x C) + (7 x H) + (1 x N) = (6 x 12.01) + (7 x 1.01) + (1 x 14.01) = 72.06 + 7.07 + 14.01 = 93.14 g/mol
So, the empirical formula mass is 93.14 g/mol.
Step 2: Calculate the ratio between the empirical formula mass and the molecular mass.
To find the ratio, divide the molecular mass by the empirical formula mass:
Ratio = molecular mass / empirical formula mass
= 372.52 g/mol / 93.14 g/mol
= 4
Step 3: Determine the molecular formula.
To determine the molecular formula, you need to multiply the subscripts of the empirical formula by the ratio calculated in Step 2.
C6H7N x 4 = C24H28N4
Thus, the molecular formula for the compound is C24H28N4.