Magnesium combines with oxygen to form magnesium oxide. A 100-gram sample of magnesium combines with 65.8 grams of oxygen. A 10-gram sample of magnesium combines with 6.58 grams of oxygen. Which point of Dalton’s atomic theory is supported by these findings? All atoms of the same element have the same mass, and atoms of different elements have different masses. All elements are composed of atoms. In a particular compound, atoms of different elements always combine in the same way.

Answer: The correct answer is in a particular compound, atoms of different elements always combine in the same way.Explanation:Postulates of Dalton's theory were:Matter is made up of indivisible particle which are known as atoms.The properties of all the atoms of an element are same including its mass. It can also be said that the mass of all the atoms of an element is same while the mass of all atoms of different elements are different.Atoms of different elements combine in fixed ratio by their mass to form compounds. Atoms are neither created nor destroyed. It can also be said that in a chemical reaction, atoms can neither be created nor be destroyed.We are given a reaction of magnesium with oxygen to produce magnesium oxide.Case 1:Mass of magnesium = 100 gramsMass of oxygen = 65.8 gramsMass ratio of magnesium and oxygen = [tex]100:65.8=1.51:1[/tex]Case 2:Mass of magnesium = 10 gramsMass of oxygen = 6.58 gramsMass ratio of magnesium and oxygen = [tex]10:6.58=1.51:1[/tex]From both the cases, it is visible that magnesium and oxygen are combining in a fixed ratio by their masses to form magnesium oxide.Hence, the correct answer is in a particular compound, atoms of different elements always combine in the same way.