Answer:
1. 42.1% sodium, 18.9% phosphorus and 39% oxygen.
2.94.07 percent oxygen and 5.93 percent hydrogen.
3.72.71 percent oxygen and 27.29 percent carbon.
4.CaSO4•2H2O has an accepted value of 20.9%.
5.40.00 percent C,6.73 precent H, 53.28 precent O.
6. 60.0% carbon and 35.5% Oxygen.
Step-by-step explanation:
you find it by dividing the molar mass of the element times the number of that element over the molar mass of the compound then times by 100