When mL methanol (molar mass = 32 g; density = 0.792 g/cm³) is added to 100 mL water (density = 1 g/cm³), the following diagram is obtained. (nearest integer).

[Given: Molal freezing point depress

Question

When  mL methanol (molar mass = 32 g; density = 0.792 g/cm³) is added to 100 mL water (density = 1 g/cm³), the following diagram is obtained.   (nearest integer).

[Given: Molal freezing point depression constant of water at 273.15 K is 1.86 K kg mol⁻¹]

Canvas Classes · Accepted Answer

Strategy:
 Use the freezing point depression shown in the graph to find the molality of the methanol solution. From molality, resolve the mass, then the volume of the methanol added using its density.

Step 1: Identify  from the graph
Observing the specific graph for this standard JEE question:
 (assuming the graph zeigt relative to pure water shift).

Step 2: Calculate molality ()
.

Step 3: Determine mass of methanol required
Solvent = 100 mL = 0.1 kg.
- Moles 
- Mass

Step 4: Calculate volu

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