This quantity equals the ratio of the effective number of particles in a solution to the number of moles of solute dissolved in the solution. For 10 points each:
[10m] Name this quantity denoted by i that helps characterize colligative properties.
ANSWER: van 't Hoff factor
[10e] The van 't Hoff factor appears in the formula for the elevation of this temperature, at which a liquid turns into a gas.
ANSWER: boiling point [or boiling point elevation]
[10h] Shortly prior to van 't Hoff's work, this other chemist introduced the notion of colligative properties. Particles in a solution tend to aggregate into larger particles via this scientist's namesake "ripening."
ANSWER: Wilhelm Ostwald [Friedrich Wilhelm Ostwald; or Ostwald ripening]
<Joseph Krol , Science - Chemistry - Physical>