Combustion of 1g of an organic compound known to contain C, H and O produces 2.36g CO2, 0.64g H2O. What is the empirical formula?
a. calculate from formula percent compositions, the mass of C and total Mass of O, and the mass of H.
b. now divide each of these by the atomic mass of C, H, O, that will give you moles of each.
Now divide each of them by the lowest of the moles for C, H, or O.
That give you the mole ratio for the elements, multipy up until you get a whole number ratio.That then is the empirical formula
https://www.google.com/search?q=determinng+empirical+formula&ie=utf-8&oe=utf-8
C3H2O
To find the empirical formula of the organic compound, we need to determine the relative number of atoms of each element present in the compound. Here's how we can do it:
Step 1: Calculate the number of moles for each product:
First, let's calculate the number of moles of CO2:
Molar mass of CO2 = 12.01 g/mol (C) + 2 * 16.00 g/mol (O) = 44.01 g/mol
Number of moles of CO2 = mass of CO2 / molar mass of CO2 = 2.36 g / 44.01 g/mol
Next, let's calculate the number of moles of H2O:
Molar mass of H2O = 2 * 1.01 g/mol (H) + 16.00 g/mol (O) = 18.02 g/mol
Number of moles of H2O = mass of H2O / molar mass of H2O = 0.64 g / 18.02 g/mol
Step 2: Determine the mole ratio:
Since both CO2 and H2O are products of the complete combustion of the organic compound, their mole ratio will be equal to the mole ratio of carbon and hydrogen in the compound.
To find the mole ratio, divide the number of moles of each product by the smallest number of moles calculated. In this case, we will divide by the number of moles of H2O:
Mole ratio of CO2 to H2O = (Number of moles of CO2) / (Number of moles of H2O) = (2.36 g / 44.01 g/mol) / (0.64 g / 18.02 g/mol)
Simplifying the expression gives us:
Mole ratio of CO2 to H2O = (2.36 * 18.02) / (44.01 * 0.64)
Step 3: Convert the mole ratio to whole numbers:
To simplify the mole ratio, we need to find the smallest whole number ratio. We can do this by dividing the mole ratio by the smallest value in the ratio and rounding to the nearest whole number:
Mole ratio ≈ 2.36 * 18.02 / 0.64 * 44.01 ≈ 2H2O : 1CO2
Since we have approximately 2 moles of H2O for every 1 mole of CO2, the empirical formula can be written as C1H2O2.
Therefore, the empirical formula of the organic compound is CH2O.