What mass of ethylene glycol (C₂H₆O₂), in grams, must be added to 1.0 kg of water to produce a solution that boils at 105.0 °C?

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SORT You are given the desired boiling point of an ethylene glycol solution con- taining 1.0 kg of water and asked to find the mass of ethylene glycol you need to add to raise the boiling point. STRATEGIZE To solve this problem, use the boiling point elevation equation to cal- culate the desired molality of the solution from AT. Then use that molality to determine how many moles of ethylene glycol are needed per kilogram of water. Finally, calculate the molar mass of ethylene glycol and use it to convert from moles of ethylene glycol to mass of ethylene glycol. GIVEN: AT = FIND: g C₂H602 CONCEPTUAL PLAN AT 5.0 °C, 1.0 kg H₂O ATt=mXK₂ kg H₂O m mol C₂H6O₂ kg H₂O mol C₂H60₂ from first step RELATIONSHIPS USED g C₂H6O2 62.07 g C2₂H₂O₂ 1 mol C₂H₂O₂ C₂H6O₂ molar mass = 62.07 g/mol AT = mx K, (boiling point elevation)