What will be the molality of chloroform in the water sample which contains 15 ppm chloroform by mass?

Question

What will be the molality of chloroform in the water sample which contains 15 ppm chloroform by mass? (A) 1.25×10-4m (B) 2.5×10-4m (C) 1.5×10-3m (D) 1.25×10-5m

Tardigrade Admin · Accepted Answer

15 ppm = (15/106) × 102 = 1.5 × 10-3 g Molality of CHCl3 solution = (1.5×10-3/100) × (1000/119.5) =1.25×10-4 m

Q. What will be the molality of chloroform in the water sample which contains $15 pp m$ chloroform by mass?

$1.25 \times 1 0^{- 4} m$

$2.5 \times 1 0^{- 4} m$

$1.5 \times 1 0^{- 3} m$

$1.25 \times 1 0^{- 5} m$

$15 pp m = \frac{15}{1 0 ^{6}} \times 1 0^{2} = 1.5 \times 1 0^{- 3} g$
Molality of $C H C l_{3}$ solution $= \frac{1.5 \times 1 0 ^{- 3}}{100} \times \frac{1000}{119.5}$
$= 1.25 \times 1 0^{- 4} m$

Q. What will be the molality of chloroform in the water sample which contains 15ppm chloroform by mass?

1.25×10−4m

2.5×10−4m

1.5×10−3m

1.25×10−5m