The correct answer for the question that is being presented above is this one:
Given that: delta Tb = Kbm Kb H2O = 0.52 degrees C/m <span>delta Tf = Kfm Kf H2O = 1.86 degrees C/m </span> We need to know the formula for Molality. molality = mol solute / kg solvent
<span>We are given the amount of solute in grams Since amount of solute is given in moles, we have to convert 25 g NaCl to moles. Divide by molar mass. </span>
<span>25 g NaCl / 58.5 g/mol = 0.427 mol </span>
<span>Then, use the formula for molality. </span>
<span>molality = mol solute / kg solvent </span> <span>= 0.427 / 1 </span> <span>= 0.427 m </span>
<span>Use now the formula to get the boiling point.</span>
