In the electrochemical series written in the increasing order of reduction potential

(A) The elements which are placed above the hydrogen in the electrochemical series are stronger oxidizing agents.
(B) The elements which are placed above the hydrogen in the electrochemical series are stronger reducing agents.
(C) The elements with the positive electrode potential values lie below the hydrogen in the electrochemical series.
(D) The activity of both the metals and non-metals in the electrochemical series decreases from top to bottom.

Choose the correct answer from the options given below:

(B) and (C) only

The correct answer is Option (1) → (B) and (C) only

Let's analyze each statement:

(A) The elements which are placed above the hydrogen in the electrochemical series are stronger oxidizing agents.

• Assumption: "Above the hydrogen" means lower (more negative) E° values.
• Trend: A lower (more negative) E° means the species is less easily reduced and more easily oxidized, making it a stronger reducing agent.
• Conclusion: This statement is Incorrect.

(B) The elements which are placed above the hydrogen in the electrochemical series are stronger reducing agents.

• Assumption: "Above the hydrogen" means lower (more negative) E° values.
• Trend: Species with lower E° are stronger reducing agents. They are placed at the top of the series (when ordered by increasing reduction potential).
• Conclusion: This statement is Correct.

(C) The elements with the positive electrode potential values lie below the hydrogen in the electrochemical series.

• Reference: The SHE is at 0.00 V.
• Trend: Since the series is written in the increasing order of reduction potential, all elements with E°>0.00 V (positive electrode potentials) will be placed below hydrogen.
• Conclusion: This statement is Correct.

(D) The activity of both the metals and non-metals in the electrochemical series decreases from top to bottom.

• Metals (Reducing Activity): Reducing power (ease of oxidation) decreases from top (most negative E°) to bottom (most positive E°).
• Non-metals (Oxidizing Activity): Oxidizing power (ease of reduction) increases from top to bottom.
• Conclusion: The activity of metals decreases, but the activity of non-metals (as oxidizing agents) increases from top to bottom. Therefore, saying "the activity of both... decreases" is Incorrect.

Final Selection

The correct statements are (B) and (C).