Answer:
The experiment described illustrates the law of definite proportions. This law states that a chemical compound always contains the same elements in the same proportion by mass.
Step-by-step explanation:
In this experiment, 1.0g of oxygen combined with 5.2g of copper. This ratio of oxygen to copper (1.0g:5.2g) remains constant regardless of the amount of oxygen and copper used.
The formula for the oxide formed by the combination of 1.0g of oxygen and 5.2g of copper is CuO.
Similarly, it was discovered that 2.6g of copper combined with 1.0g of oxygen. The ratio of copper to oxygen (2.6g:1.0g) remains constant, indicating the formation of another oxide.
The formula for the oxide formed by the combination of 2.6g of copper and 1.0g of oxygen is Cu2O.
Therefore, the experiment illustrates the law of definite proportions, and the formulas for the oxides are CuO and Cu2O.