40 g / 56 g X 100%
40 g / 56 g X 100%
The percent composition of calcium oxide (CaO) is 71.5% calcium (Ca) and 28.5% oxygen (O).
The molar mass of CaSO4 is 136.14 g/mol. The molar mass of Ca in CaSO4 is 40.08 g/mol. To find the percent composition of Ca by mass, divide the molar mass of Ca by the molar mass of CaSO4 and multiply by 100. This gives a percent composition of approximately 29.4%.
The balanced equation for this reaction is: Ca(OH)2 --> CaO + H2O.
The balanced equation for the addition of water to quicklime, which is calcium oxide (CaO), is: CaO + H2O → Ca(OH)2.
40 g / 56 g X 100%
The percent composition of calcium oxide (CaO) is 71.5% calcium (Ca) and 28.5% oxygen (O).
40 g / 56 g X 100%
It would seem that because calcium and oxygen are in equal molar ratio for this compound that it would be 50 percent. But that is incorrect, because they each have differing molar masses. Oxygen has a molar mass of 16.000 and calcium has a molar mass of 40.078. So calcium is 40.078/56.078, which is 71.47 percent.
The molar mass of CaSO4 is 136.14 g/mol. The molar mass of Ca in CaSO4 is 40.08 g/mol. To find the percent composition of Ca by mass, divide the molar mass of Ca by the molar mass of CaSO4 and multiply by 100. This gives a percent composition of approximately 29.4%.
The percent composition by element of Ca(C2H3O2)2 is calcium 25.339%, hydrogen 3.824%, carbon 30.375%, and oxygen 40.462%.
CaO
Ca + O2 gives 2CaO
Molecular mass of calcium oxide = calcium (40,078) + oxygen (15,9994) = 56,0774 56,0774 CaO--------------40,078 Ca 100 g CaO-----------------x g Ca x = (40,078 x 100)/56,o774 = 71,469 % Ca
40 g / 56 g X 100%
The balanced equation for this reaction is: Ca(OH)2 --> CaO + H2O.
The balanced equation for the addition of water to quicklime, which is calcium oxide (CaO), is: CaO + H2O → Ca(OH)2.