Boiling point elevation- what am I doing wrong? braniacs, help!?

Dr A shows you the math quite nicely - now to fully point out your boo-boo so you get the correct answer the next time. You used the correct calculation for a NON-ELECTROLYTE substance. With the electrolytes like CaCl2, you have to take into account the fact that each molecule of CaCl2 dissociates into 3 IONS, so you have triple the effect that you would see with a substance that doesn't dissociate..............................… you had used something like sugar, your answer of 0.4 would have been fairly close..........................if you had used sodium chloride, it would be 100.9 C or so BP, and if you had used lanthanum trichloride, it would be 101.8 C or so for the BP.