Question

Given below are two statements: Assertion (A): All metals are good conductors of electricity. Reason (R): Metals contain free electrons that allow electric current to pass. Choose the most appropriate answer.

• A. Both (A) and (R) are correct and (R) is the correct explanation of (A).
• B. Both (A) and (R) are correct but (R) is not the correct explanation of (A).
• C. (A) is correct but (R) is not correct.
• D. (A) is not correct but (R) is correct.

Hint:

Metals conduct electricity because they have mobile free electrons.

Answer 1

The Correct Option is A

Step 1: Understanding the Question:

• This question involves an Assertion and a Reason regarding the physical properties and electrical conductivity of metallic elements.

• We must evaluate the accuracy of both statements based on physical principles of metallic bonding and charge transport.

Step 2: Detailed Explanation:

• Evaluating Assertion (A): Metals are chemically characterized by their ability to readily lose valence electrons. In the solid state, metallic atoms form a crystalline lattice where positive ions are surrounded by a shared “sea of mobile valence electrons.” This structural arrangement makes metals excellent conductors of electricity and heat. Thus, Assertion (A) is scientifically correct.

• Evaluating Reason (R): Electric current is defined as the net rate of flow of electric charge through a conductor. In metals, the charge carriers are the free, delocalized electrons that exist in the conduction band. When an electric potential difference (voltage) is applied across a metal wire, these free electrons experience an electrostatic force and drift toward the positive terminal, creating an electric current. Thus, Reason (R) is scientifically correct.

• Causal Connection: The microscopic presence of free electrons (R) directly explains the macroscopic phenomenon of electrical conductivity in metals (A). Therefore, Reason (R) is the correct and complete explanation of Assertion (A).

• Consequently, the correct choice is Option (A).

Step 3: Final Answer:
The correct option is (A).