Answer:
Empirical formula is Na₂CO₃
Molecular formula is Na₂CO₃
Explanation:
Percentage compositions of the elements;
Sodium = 46%
Carbon = 12 %
Oxygen = 42%
To determine empirical formula, we calculate the mole ratio first.
mole ratio = % mass/atomic mass; where the atomic masses of the elements are : Na = 23 u, C = 12 u and O = 16 u.
mole ratio: Na = 46/23; C = 12/12; O = 42/16
mole ratio (Na : C : O) = 2 : 1 : 2.6
approximate mole ratio = 2 : 1 :3
Therefore, empirical formula of compound is Na₂CO₃
To determine the molecular formula;
molecular formula or mass = n(empirical formula or mass)
n = molecular mass/empirical mass
molecular mass = 106 u,
empirical mass = 23*2 + 12 + 16*3 = 106 u
then, n = 106/106 = 1
therefore, molecular formula = 1 * (Na₂CO₃) = Na₂CO₃
