The number of correct statement from the following is
(A) conductivity always decreases with decrease in concentration for both Strong and weak electrolytes.
(B) the number of ions per unit volume that carry current in a solution Increases on dilution
(C) molar conductivity increases with decrease in concentration
(D) the variation in molar conductivity is different for strong and weak electrolytes .
(E) for weak electrolytes, the change in molar conductivity with dilution is due to decrease in degree of dissociation

(A) Conductivity always decreases with decrease in concentration for both strong and weak electrolytes.

This statement is true. Conductivity is defined as the ability of a solution to conduct electricity, and it depends on the concentration of ions in the solution. As the concentration of ions decreases, the conductivity of the solution also decreases, regardless of whether the electrolyte is strong or weak.

(B) The number of ions per unit volume that carry current in a solution increase on dilution.

This statement is false. The number of ions per unit volume in a solution decrease on dilution, because the total number of ions in the solution remains the same, but the volume increases.

(C) Molar conductivity increases with decrease in concentration.

This statement is generally true. Molar conductivity is a measure of the ability of an electrolyte to conduct electricity, and it depends on both the concentration of the electrolyte and the mobility of the ions. As the concentration of the electrolyte decreases, the molar conductivity increases because the ions become more separated from each other, and the electrostatic interactions between them become weaker, allowing them to move more freely in the solution.

(D) The variation in molar conductivity is different for strong and weak electrolytes.

This statement is true. The variation in molar conductivity with concentration is different for strong and weak electrolytes. Strong electrolytes dissociate completely in solution, so their molar conductivity increases rapidly with dilution, while weak electrolytes dissociate only partially, so their molar conductivity increases more slowly with dilution.

(E) For weak electrolytes, the change in molar conductivity with dilution is due to decrease in degree of dissociation.

This statement is false. For weak electrolytes, the change in molar conductivity with dilution is due to an increase in the degree of dissociation, not a decrease.

Therefore, there are 3 correct statements in the given options, namely (A), (C), (D).