Final answer:
The molecular mass of sodium trioxocarbonate (IV) decahydrate is calculated by adding up the atomic masses of sodium, carbon, oxygen, and water molecules, resulting in a molecular mass of approximately 286 g/mol. Therefore, the correct answer is b) 286 g/mol.
Step-by-step explanation:
The molecular mass of sodium trioxocarbonate (IV) decahydrate, commonly known as sodium carbonate decahydrate (Na2CO3·10H2O), is calculated by summing the atomic masses of all atoms present in the formula. This includes 2 sodium (Na) atoms, 1 carbon (C) atom, 3 oxygen (O) atoms, and 10 water molecules (10H2O).
Using the atomic masses from the periodic table:
Sodium (Na) = 22.990 g/mol
Carbon (C) = 12.011 g/mol
Oxygen (O) = 15.999 g/mol
Hydrogen (H) = 1.008 g/mol
The calculation is:
2(22.990) + 12.011 + 3(15.999) + 10(2(1.008) + 15.999) = 285.22 g/mol
Therefore, the correct answer is b) 286 g/mol.