Direction : In the following questions, a statement of assertion (A) ...
Number of atoms present in a molecule of a gaseous element is called atomicity. e.g., O2 has two atoms and hence, its atomicity is 2.
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Direction : In the following questions, a statement of assertion (A) ...
Assertion (A): Atomicity of oxygen is 2.
Reason (R): 1 mole of an element contains 6.023 x 10^23 atoms.
The correct answer is option 'B' - Both assertion (A) and reason (R) are true, but reason (R) is not the correct explanation of assertion (A).
Explanation:
Atomicity of Oxygen:
- Atomicity refers to the number of atoms present in a molecule of an element.
- Oxygen (O) is a diatomic molecule, which means it exists as O2 in its natural state.
- Therefore, the atomicity of oxygen is 2, as it consists of two oxygen atoms bonded together.
Mole Concept:
- The mole concept is a fundamental concept in chemistry that helps to relate the mass of a substance to the number of particles (atoms, molecules, ions) it contains.
- According to Avogadro's law, 1 mole of any substance contains 6.023 x 10^23 particles. This number is known as Avogadro's number or the Avogadro constant.
Explanation of the Reason:
- The reason given is correct but it does not provide the correct explanation for the atomicity of oxygen.
- The reason states that 1 mole of an element contains 6.023 x 10^23 atoms, which is true. It means that if we have 1 mole of any element, it will contain Avogadro's number of atoms.
- However, this statement does not directly explain why the atomicity of oxygen is 2.
- The atomicity of oxygen is based on the fact that oxygen exists as O2, a diatomic molecule, in its natural state. This means that in 1 molecule of oxygen, there are 2 oxygen atoms bonded together.
- The reason given does not provide this specific information about the atomicity of oxygen.
Therefore, both the assertion and reason are true, but the reason does not correctly explain the assertion. Hence, the correct answer is option 'B'.
Direction : In the following questions, a statement of assertion (A) ...
Both are different sentences...not related
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