I have to find the molecular formula for As2O3, to do so I have to divide its molecular mass by its empirical mass. I have worked ou that its molecular mass is 197.9 g/mol. How would I find its empirical mass, is it not the same as its molecular mass? Many thanks
I have 197.84. If the molar mass is 197.84, then the empirical mass is the same since As2O3 is already in its simplest form.
Excellent, many thanks for your help.
You're welcome! I'm glad I could help.
To clarify, the empirical formula represents the simplest ratio of atoms in a compound. In the case of As2O3, its empirical formula is already in the simplest form, indicating that each molecule contains two atoms of arsenic (As) and three atoms of oxygen (O).
The molecular formula, on the other hand, represents the actual number of atoms of each element in the compound. To determine the molecular formula, you would need to know the molar mass of the compound.
In your case, the given molar mass of As2O3 is 197.9 g/mol. If this is the accurate molar mass, then the empirical mass and molecular mass would be the same. Thus, the molecular formula for As2O3 is also As2O3, meaning each molecule contains two atoms of arsenic and three atoms of oxygen, with a total molar mass of 197.9 g/mol.
If you had a different molar mass for As2O3, you would need to calculate the empirical mass by dividing the molar mass by the greatest common divisor of the atomic masses. The resulting ratio would be used to determine the empirical formula.
I hope this clears up any confusion. Let me know if you have any further questions!