Answer to Question #97751 in General Chemistry for Jamie

Question

1.00 mL of a 3.80 × 10–4 M solution of oleic acid is diluted with 9.00 mL of petroleum ether, forming solution A. Then 2.00 mL of solution A is diluted with 8.00 mL of petroleum ether, forming solution B. What is the concentration of solution B?

Answer 1

$$M_1 V_1 = M_2 V_2 \\ M_2 =\frac{ M_1 V_1} {V_2}$$

After first dilution,

$$M_2=\frac {(3.95\times10^{−4 }mol\ L^{-1} )(0.001L)} {.0100L} = 3.95\times10^{−5} M$$

After second dilution,

$M_3=\frac{(3.95\times10^{-5})(0.002)}{0.010}=7.90\times10^{-6}\ M$