Question

We have two solutions, one is 1 L of 0.1 M $NaCl$ and the other is 2 L of 0.2 M $CaC{l}_2$. Using only these two solutions, what maximum volume of a solution can be prepared, which has $\left[C{l}^{-}\right]=0.34M?$

[Given: Both electrolytes are strong.]

• A. 2.5 L
• B. 2.4 L
• C. 2.3 L
• D. 2.65 L

Answer 1

The correct option is D 2.65 L

Let x and y represnts the volumes of 0.1 M NaCl and 0.2 M $CaC{l}_2$ used to prepare a solution which is 0.34M in chloride ion.

Hence, $\frac{0.1x+0.4y}{x+y}=0.34$

The total volume $V_g=(x+y)$ will be maximum when $y=4x$ since concentration is 4 times in case of $CaC{l}_2$ in case of chloride ion.

Substituting ans olving the above equation we get

Thus $y=2L$ and $x=\frac{1}{2}L$.

The maximum volume of solution that can be prepared is 2.5 L