The boiling point of a solution depends on the concentration of solute in the solution. When a solute is dissolved in a solvent, it raises the boiling point of the solution compared to the boiling point of the pure solvent. This is because the solute particles interfere with the hydrogen bonding between the solvent molecules, making it more difficult for the solvent to evaporate.
In this case, 180.00 grams of C6H12O6 (glucose) has been dissolved in 1,000.0 grams of water, so the concentration of glucose in the solution is 180.00 g / 1000.0 g = 0.18 g/g, or 18%.
The boiling point of a solution can be estimated using the formula ΔTb = Kb x molality, where ΔTb is the change in boiling point, Kb is the molal boiling point constant for water (0.512 °C/m), and molality is the concentration of solute in the solution in moles per kilogram of solvent.
Using this formula, the change in boiling point for the glucose solution can be calculated as follows:
ΔTb = Kb x molality = 0.512 °C/m x (0.18 moles/kg) = 0.093 °C
The boiling point of pure water at 1 atmosphere is 100.0 °C, so the boiling point of the glucose solution is 100.0 °C + 0.093 °C = 100.093 °C.
Therefore, the answer to the question is (3) 99.48°C.