Estimate the boiling point of 250 cm3 of water to which 12.6 g of phenol(C6H5OH) has been added. Treat the solution as ideal.( water of boiling point elevation is 0.51K/mol)

mols phenolphthalein = grams/molar mass = ?

molality = m = mols/kg solvent
Then delta T = Kb*m. You have m and Kb, solve for delta T.
Then boiling point = 100 + delta T.

To estimate the boiling point of the water-phenol solution, we need to consider the concept of boiling point elevation.

Boiling point elevation occurs when a solute is added to a solvent, causing an increase in the boiling point of the solution compared to the pure solvent. The change in the boiling point can be calculated using the equation:

ΔTb = Kb * molality

where:
ΔTb is the change in boiling point
Kb is the molal boiling point elevation constant (0.51 K/mol for water)
molality is the concentration of the solute in mol/kg

First, we need to calculate the molality of the phenol in the water-phenol solution. Molality can be calculated using the formula:

molality = moles of solute / mass of solvent in kg

1. Calculate the moles of phenol (C6H5OH):
moles = mass / molar mass
molar mass of C6H5OH = 94.11 g/mol

moles of C6H5OH = 12.6 g / 94.11 g/mol

2. We need the mass of the solvent (water) in kg:
mass of water = 250 cm3 = 250 g (since 1 cm3 of water = 1 g)
mass of water in kg = 250 g / 1000 = 0.25 kg

3. Calculate the molality:
molality = moles of C6H5OH / mass of water in kg

4. Calculate the change in boiling point:
ΔTb = Kb * molality

Now, we can calculate the change in boiling point and add it to the boiling point of pure water (100°C or 373.15 K) to get the estimated boiling point of the water-phenol solution.