Question

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 1

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 grams

Mass of oxygen = 65.8 grams

Mass ratio of magnesium and oxygen = $100:65.8=1.51:1$

• Case 2:

Mass of magnesium = 10 grams

Mass of oxygen = 6.58 grams

Mass ratio of magnesium and oxygen = $10:6.58=1.51:1$

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.

Answer 2

Answer:

In a particular compound, atoms of different elements always combine in the same way.

Step-by-step explanation:

Dalton's atomic theory postulate:

1.All matter consist of indivisible particles called atoms.

2.Atoms of same element are identical in shape and mass. Atoms of different element are different in shape and mass.

3.Atoms cannot be created or destroyed.

4.Atoms of different elements may combine with each other in a fixed , simple, whole number ratios to form compounds.

5.Atoms is the smallest unit of matter that can take part in  a chemical reaction.

Mass of magnesium in a sample=100 g

Mass of oxygen in a  sample=65.8 g

Ratio of Mg to O=100:65.8=1.52:1

Mass of magnesium in other sample=10 g

Mass of oxygen in other sample=6.58 g

Ratio of Mg to O=10:6.58=1.52:1

Hence, the ratio of Magnesium to oxygen in each sample=1.52:1

Therefore, the point supported by given information is

In a particular compound, atoms of different elements always combine in the same way.

Answer:In a particular compound, atoms of different elements always combine in the same way.