The chemical formula of Iron (III) Sulfide is FeSO3. This element or compound has another name which is <span>ferric sulfide or sesquisulfide.</span>
Answer: The mass percentage of 
is 5.86%
Explanation:
To calculate the mass percentage of in the sample it is necessary to know the mass of the solute ( in this case), and the mass of the solution (pesticide sample, whose mass is explicit in the letter of the problem).
To calculate the mass of the solute, we must take the mass of the 
precipitate. We can establish a relation between the mass of and using the stoichiometry of the compounds:
Since for every mole of Tl in there are two moles of Tl in , we have:
Using the molar mass of we have:
Finally, we can use the mass percentage formula:
We are given with an element Iron, Fe, with a mass of 235.45 g. We are tasked to solve for its corresponding molar mass in mol. We need to find first the molecular weight of Iron, that is
Fe= 55.845 g/mol
With 235.45 g sample, its corresponding mol is
mol Fe= 235.45 g x 1 mol/55.845 = 4.22 mol Fe
Therefore, molar mass of Iron is 4.22 mol
B:Molecules must collide.
Why: They have to collide so the chemical bonds can break.
Physical: slicing or cutting and painting it with a different color
Chemical: rusting
