I think because each element has its own number of protons and neutrons, giving it its own atomic number and mass (correct me if I’m wrong please)
All matter is made up of particles called atoms and molecules (as opposed to being continuous or just including particles). On the following page, the idea is stated as one of four concepts in Dalton's theory: “All matter is composed of tiny, indivisible particles called atoms” (p. 158s).
The gas is confined in 3.0 L container ( rigid container) ⇒ the volume remains constant when the temperature is increased from from 27oC to 77oC and therefore V1=V2 .
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Hope it helps you please mark as brainlist</h2>
