The percentage by mass of water in Na2CO3.10H2O from the calculation is 62.9%
The term percentage by mass refers to the amount of a particular moiety by mass in a molecule.
In this case, we know that the molar mass of Na2CO3.10H2O is 286 g/mol the molar mass of the 10 moles of water is 180 g/mol hence the percentage by mass of water in the compound is; 180 g/mol /286 g/mol * 100/1 = 62.9%
Learn more about percentage by mass: https://brainly.com/question/16885872
#SPJ2
