Final answer:
The mass percent of oxygen in zinc bromate is calculated by finding the ratio of the mass of oxygen to the total molar mass of zinc bromate (Zn(BrO3)2) and multiplying by 100, resulting in 29.90%.
Step-by-step explanation:
To calculate the mass percent of oxygen in zinc bromate, we first need to determine the formula for zinc bromate, which is Zn(BrO3)2. To find the percent composition by mass of oxygen, we would do the following:
- Calculate the molar mass of zinc bromate. This involves adding the atomic masses of all the atoms in the compound: Zn = 65.38 g/mol, Br = 79.904 g/mol, and O = 16.00 g/mol. The total molar mass is thus: M(Zn(BrO3)2) = 65.38 + (2 x 79.904) + (6 x 16.00) = 321.095 g/mol.
- Determine the mass of oxygen in one mole of zinc bromate: 6 x 16.00 g/mol = 96.00 g/mol.
- Finally, divide the mass of oxygen by the total mass of zinc bromate and multiply by 100 to get the percent by mass: (96.00 / 321.095) x 100 = 29.90%.
Therefore, the mass percent of oxygen in zinc bromate is 29.90%.
This calculation makes sense because the sum of the percentage composition of all elements in a compound should add up to 100%. By mass, the compound is mostly composed of zinc and bromine with a significant percentage being oxygen.