Calculate the empirical formula for each of the following natural flavors based on their elemental mass percent composition.
vanillin (responsible for the taste and smell of vanilla): C 63.15% H 5.30% O 31.55%.
see below
To calculate the empirical formula of a compound based on its elemental mass percent composition, we need to determine the simplest whole number ratio of atoms in the compound.
Let's start by assuming we have 100 grams of the natural flavor.
Given:
Mass percent of carbon (C) = 63.15g/100g * 100 = 63.15%
Mass percent of hydrogen (H) = 5.30g/100g * 100 = 5.30%
Mass percent of oxygen (O) = 31.55g/100g * 100 = 31.55%
Next, we need to convert the mass percent to moles by dividing by the atomic masses of each element:
Atomic mass of carbon (C) = 12.01 g/mol
Moles of carbon (C) = (63.15g/100g) / 12.01 g/mol = 0.526 moles
Atomic mass of hydrogen (H) = 1.01 g/mol
Moles of hydrogen (H) = (5.30g/100g) / 1.01 g/mol = 0.052 moles
Atomic mass of oxygen (O) = 16.00 g/mol
Moles of oxygen (O) = (31.55g/100g) / 16.00 g/mol = 0.197 moles
Now, divide the moles of each element by the smallest mole value:
Carbon (C) = 0.526 moles / 0.052 moles = 10.12 (approximately)
Hydrogen (H) = 0.052 moles / 0.052 moles = 1
Oxygen (O) = 0.197 moles / 0.052 moles = 3.79 (approximately)
The empirical formula is the simplest whole number ratio of atoms in the compound. Thus, the empirical formula for vanillin is approximately C₁₀H₁O₄.