How many of the following statements are correct:
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Molar conductivity increases with dilution, especially for weak electrolytes, due to in creased ion dissociation.
- Conductivity (K) decreases with increase in dilution for both strong and weak electrolyte.
- Molar conductivity increases with increase in dilution for both strong and weak electrolyte.
- Molar conductivity increases with increase in βπΌβ for weak electrolyte.
- Change in molar conductivity is same for both strong and weak electrolyte with increase in dilution.
The Correct Option is A, B, C
Solution and Explanation
Analysis of Conductivity and Molar Conductivity
(A) Correct: Conductivity decreases for both strong and weak electrolytes with dilution due to fewer ions per unit volume.
(B) Incorrect: On dilution, the ion concentration decreases, reducing the current-carrying ions per unit volume.
(C) Correct: Molar conductivity increases as more ions dissociate per mole on dilution.
(D) Correct: Strong electrolytes show slight variation, while weak electrolytes exhibit significant variation due to dissociation.
(E) Incorrect: For weak electrolytes, dilution increases dissociation, significantly impacting molar conductivity.
Final Answer:
The correct options are: (A), (B), (C).
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Concepts Used:
Electrochemical Cells
An electrochemical cell is a device that is used to create electrical energy through the chemical reactions which are involved in it. The electrical energy supplied to electrochemical cells is used to smooth the chemical reactions. In the electrochemical cell, the involved devices have the ability to convert the chemical energy to electrical energy or vice-versa.
Classification of Electrochemical Cell:
Cathode
- Denoted by a positive sign since electrons are consumed here
- A reduction reaction occurs in the cathode of an electrochemical cell
- Electrons move into the cathode
Anode
- Denoted by a negative sign since electrons are liberated here
- An oxidation reaction occurs here
- Electrons move out of the anode
Types of Electrochemical Cells:
Galvanic cells (also known as Voltaic cells)
- Chemical energy is transformed into electrical energy.
- The redox reactions are spontaneous in nature.
- The anode is negatively charged and the cathode is positively charged.
- The electrons originate from the species that undergo oxidation.
Electrolytic cells
- Electrical energy is transformed into chemical energy.
- The redox reactions are non-spontaneous.
- These cells are positively charged anode and negatively charged cathode.
- Electrons originate from an external source.