The resistance of a solution ' A' is 40 ohm and that of solution ' B ' is 70 ohm, both solutions being taken in the same conductivity cell. If equal volumes of solutions ' A' and ' B 'are mixed, what will be the resistance of the mixture using the same cell? (Assume that there is no increase in the degree of dissociation of ' A' and ' B 'on mixing.)

Question

The resistance of a solution ' A' is 40 ohm and that of solution ' B ' is 70 ohm, both solutions being taken in the same conductivity cell. If equal volumes of solutions ' A' and ' B 'are mixed, what will be the resistance of the mixture using the same cell? (Assume that there is no increase in the degree of dissociation of ' A' and ' B 'on mixing.) (A) 50.9 ohm (B) 101.8 ohm (C) 110 ohm (D) 50 ohm

Tardigrade Admin · Accepted Answer

(1/R)=(70+40/2800) Since equal valume are mixed R=(2800/110) × 2=50.9 ohm

50.9 ohm

101.8 ohm

110 ohm

50 ohm

R1​=280070+40​ Since equal valume are mixed R=1102800​×2=50.9ohm

$\frac{1}{R} = \frac{70 + 40}{2800}$
Since equal valume are mixed
$R = \frac{2800}{110} \times 2 = 50.9 o hm$