Bra2ndesMarehmjo
Answered

A 250-mL aqueous solution contains 1.56 mc025-1.jpg 10–5 g of methanol and has a density of 1.03 g/ml. What is the concentration in ppm?

A6.1 x 10^-8 ppm
B1.5 x 10^-5 ppm
C0.061 ppm
D15 ppm

Verified Answer :

taskmasters

I think the correct answer from the choices presented above is option A. A 250-mL aqueous solution contains 1.56 g of methanol and has a density of 1.03 g/ml. Its concentration in ppm is  6.1 x 10^-8 ppm. Hope this answers the question.

Answer: The correct option is C.

Explanation:

ppm : It is used to measure the concentration of solute in a given volume of solution. ppm is basically parts per million.

Formula used :

\(ppm=\frac{\text{Mass of solute (in mg)}}{\text{Volume of solution (in L)}}\)

We are given :

Mass of methanol = \(1.56\times 10^{-5}g=1.56\times 10^{-2}mg\)

(Conversion Factor : 1g = 1000mg)

Volume of solution = 250 mL = 0.250L   (Conversion Factor : 1L = 1000mL)

Now put all the given values in above equation, we get:

\(ppm=\frac{1.56\times 10^{-2}mg}{0.250L}\)

Concentration of methanol = 0.061ppm

Hence, the correct option is C.