Tawfik

yes, if the earth stop spinning the half of the world is in a lonnnnnnnnng cold darkness "night" and the other half is in a lonnnnnnnng hot day... note: in my society we believe that this day "the earth stop spinning" will come...and than the earth will spin in the other direction.

Hi, they said in the question that: naphthalene is nonvolatile (the nonvolatile compound don't have a vapor pressure..)...so in ur exercise solution u shouldn't take consideration of naphta's pressure.....: 0.459 atm * X_Nap. -{0.10} or 0.459 * 0 = 0 Partial Pressure Nap. 0.459 atm * X_Eth. -{0.90} or 0.459 * 0.90 = 0.4131 Partial Pressure Eth. is the vapor pressure of solution.