We’re being asked to determine the empirical formula for estrone composed of C, H, and O given the combustion analysis.
Recall that in combustion analysis, a compound reacts with excess O2 to form products.
For a compound composed of C, H, and O, the reaction looks like this:
CxHyOz + O2 (excess) → x CO2 + y H2O
This means we need to do the following steps:
Step 1: Calculate the mass of C and H in the compound.
Step 2: Calculate the mass of O in the compound.
Step 3: Calculate the moles of C, H and O
Step 4: Determine the lowest whole number ratio of C, H, and O to get the empirical formula.
Step 5: Get the ratio of the molar mass and empirical mass to determine the molecular formula.
Estrone, which contains only carbon, hydrogen, and oxygen, is a female sexual hormone that occurs in the urine of pregnant women. Combustion analysis of a 1.893-g sample of estrone produced 5.543 g of CO2 and 1.388 g H2 O. The molar mass of estrone is 270.36 g/mol .
Find the molecular formula for estrone.