Calculate the mass of a non-volatile solute (molar mass 40 g mol⁻¹) which should be dissolved in 114 g octane to reduce its vapour pressure to 80%.

Open in App

Solution

Let the vapour pressure of pure octane be

Then, the vapour pressure of the octane after dissolving the non-volatile solute is

Molar mass of solute, M₂ = 40 g mol⁻¹

Mass of octane, w₁ = 114 g

Molar mass of octane, (C₈H₁₈), M₁ = 8 × 12 + 18 × 1

= 114 g mol⁻¹

Applying the relation,

Hence, the required mass of the solute is 8 g.

Suggest Corrections

335

Similar questions

QUESTION 2.18

Calculate the mass of a non-volatile solute (molar mass $40 g m o l^{- 1}$ ) which should be dissolved in 114g octane to reduce its vapour pressure to $80 %$ .

Q. Calculate the weight of a non-volatile solute

(m o l . / w t . 40)

which should be dissolved in

114 g

octane to reduce its vapour pressure to

80

Q. Calculate the mass of a non-volatile solute of molecular mass 40, which should be dissolved in 114 g octane to reduce the vapour pressure to

80 %

Q. The mass of non-volatile, non-electrolyte solute (molar mass

50 g {m o l}^{- 1}

) needed to be dissolved in

114 g

octane to reduce its vapour pressure to

75

%, is ___________.

Q. The weight of a non-volatile solute (m. wt. 40). Which should be dissolved in

114 g

octane to reduce its vapour pressure to

80 %

, is-

Join BYJU'S Learning Program

Calculate the mass of a non-volatile solute (molar mass 40 g mol−1) which should be dissolved in 114 g octane to reduce its vapour pressure to 80%.

Calculate the mass of a non-volatile solute (molar mass 40 g mol⁻¹) which should be dissolved in 114 g octane to reduce its vapour pressure to 80%.