Three samples of sodium carbonate Na2CO3 obtained from various sources were analyzed for elemental compositions. Show that the data below illustrate the law of constant composition. Sample-1 contains 1.95 g Sodium, 0.51 g Carbon, and 2.04 g Oxygen.

Sample-2 contains 1.52 g Sodium, 0.40 g Carbon, and 1.58 g Oxygen.

Sample-3 yields 1.30 g Sodium, 0.34 g Carbon, and 1.36 g Oxygen.


Three samples, X, Y, and Z, were analyzed for elemental compositions. Sample X is found to contain 1.00 g Calcium, 0.30 g Carbon, and 1.20 g Oxygen. Sample Y contains 1.41 g Calcium, 0.84 g Carbon, and 2.25 g Oxygen. Sample Z contains 1.60 g Calcium, 0.48 g Carbon, and 1.92 g Oxygen.

Determine whether X, Y, and Z are samples of the same compound, they are samples of different compounds, or only two of them belong to the same compound.