A sample of pure water irrespective of its source contains 88.89% oxygen and 11.11% hydrogen by mass.The data supports:Law of conservation of massLaw of constant compositionDalton’s atomic theoryAvogadro’s law

The data supports the Law of Constant Composition. This law, also known as the Law of Definite Proportions, states that a given compound always contains exactly the same proportion of elements by mass. In this case, pure water (H2O) always contains 88.89% oxygen and 11.11% hydrogen by mass, regardless of its source. This is consistent with the Law of Constant Composition.

The Law of Conservation of Mass is not directly supported by this data, as it states that matter cannot be created or destroyed, only rearranged. This data does not provide information about any chemical reactions or changes in mass.

Dalton's Atomic Theory is also not directly supported by this data. While one of Dalton's postulates is that atoms combine in simple whole number ratios to form compounds (which is consistent with the composition of water), the data provided does not specifically address this or any of Dalton's other postulates.

Avogadro's Law states that equal volumes of gases, at the same temperature and pressure, contain the same number of molecules. This data about the composition of water does not provide any information about volumes of gases, so Avogadro's Law is not directly supported by this data.