The question asks to identify a postulate of Dalton's Atomic Theory. We need to recall the main points of Dalton's theory and compare them with the given options.
Correct Option: D) Atoms of the same element are identical in mass and properties; atoms of different elements differ in mass and properties. This is a direct statement of two core postulates of Dalton's Atomic Theory. Dalton proposed that all atoms of a specific element are exactly alike, and atoms of different elements are fundamentally different from each other.
The question asks to identify which postulate of Dalton's Atomic Theory directly explains the Law of Constant Proportions. We need to recall Dalton's postulates and the Law of Constant Proportions to find the correct match.
A) Atoms of the same two elements always combine in the same fixed ratio to form a particular compound
This postulate directly explains the Law of Constant Proportions. If atoms of specific elements combine in a fixed whole-number ratio to form a particular compound, and each type of atom has a characteristic mass, then the mass ratio of the elements in that compound will also be constant.
The question asks to identify a limitation of Dalton's Atomic Theory. We need to recall the postulates of Dalton's theory and its subsequent failures or modifications based on later discoveries.
Correct Option: C) It could not explain the existence of isotopes (atoms of same element with different masses)
The question asks about the fate of atoms during a chemical reaction according to Dalton's Atomic Theory. We need to recall the postulates of Dalton's theory, particularly those related to chemical reactions.
B) Atoms are rearranged — old bonds break and new bonds form — but atoms themselves are neither created nor destroyed
This statement perfectly aligns with Dalton's Atomic Theory. It emphasizes that chemical reactions involve the breaking of existing bonds and the formation of new ones, leading to a rearrangement of atoms, but the atoms themselves retain their identity and are conserved.
The question asks about the origin of the chemical symbol 'Na' for Sodium. Chemical symbols are often derived from the element's name in English, Latin, or sometimes Greek. We need to identify which language 'Na' comes from.
C) Latin name 'Natrium'
The chemical symbol 'Na' for Sodium is derived from its Latin name, 'Natrium'. This is a common practice in chemistry, where symbols for several elements are based on their Latin or sometimes Greek names, rather than their modern English names.
The question asks for the correct chemical symbol for the element Potassium. This requires knowledge of the standard chemical symbols used in the periodic table.
Correct Option: D) The chemical symbol for Potassium is K. This symbol is derived from its Latin name, Kalium.