Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.

Assertion(A): The noble gases are inactive.
Reason(R): These gases have a closed shell structure.
a)
Both A and R are true and R is the correct explanation of A
b)
Both A and R are true but R is NOT the correct explanation of A
c)
A is true but R is false
d)
A is false and R is True
Correct answer is option 'A'. Can you explain this answer?

Question

Directions: In the following questions, A statement of Assertion (A) is followed by a statement of Reason (R). Mark the correct choice as.

Assertion(A): The noble gases are inactive.
Reason(R): These gases have a closed shell structure.

a)
Both A and R are true and R is the correct explanation of A
b)
Both A and R are true but R is NOT the correct explanation of A
c)
A is true but R is false
d)
A is false and R is True

Correct answer is option 'A'. Can you explain this answer?

Answer

Assertion: The noble gases are inactive.
Reason: These gases have a closed shell structure.

Explanation:
The noble gases, also known as inert gases, are a group of chemical elements that include helium (He), neon (Ne), argon (Ar), krypton (Kr), xenon (Xe), and radon (Rn). These gases are called 'noble' or 'inert' because they are generally unreactive or inactive.

Explanation of Assertion:
The assertion that noble gases are inactive is true. Noble gases have a complete outer electron shell, which gives them a stable electron configuration. Their outer electron shell is completely filled with electrons, meaning they do not readily gain or lose electrons to form chemical bonds with other elements. This makes them highly stable and unreactive under normal conditions. Their closed shell structure prevents them from easily participating in chemical reactions, explaining their lack of reactivity.

Explanation of Reason:
The reason given for the assertion is also true. The closed shell structure of noble gases refers to their outer electron shell being completely filled with electrons. This configuration is achieved by having the maximum number of electrons allowed in each energy level of the electron shell. For example, helium has two electrons in its outer shell, while neon, argon, and other noble gases have eight electrons in their outer shell.

The closed shell structure of noble gases provides them with a high level of stability. The filled outer electron shell results in a balanced electrostatic force, which prevents the noble gases from readily gaining or losing electrons. As a result, they do not easily form chemical bonds with other elements, making them chemically inactive.

Conclusion:
Both the assertion and the reason are true, and the reason correctly explains why noble gases are inactive. The closed shell structure of these gases provides them with stability and prevents them from participating in chemical reactions. Hence, option A is the correct answer.

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