Question

Which solution will have a higher boiling point: A solution containing 15 grams of sucrose (C12H22O11) in 25 grams of water or a solution containing 35 grams of sodium chloride in 500 grams of water?

Answer 1

Would you not expect the SALT rather than the SUGAR solution to have the greater boiling point...?

Explanation:

The sucrose solution is LESS concentrated than the salt solution, and will CAUSE LESS boiling point elevation than the more concentrated salt particles.

`["Sucrose"]=((15*g)/(342.3*g*mol^-1))/(25xx10^-3*kg)=1.75*mol*kg^-1`

Moreover, salt undergoes a chemical reaction in water. It speciates to give TWO particles, ONE ANION, and ONE CATION...

`NaCl(s) stackrel(H_2O)rarr Na^+ + Cl^-`

`["Ions in solution"]_"NaCl"=((2xx35.0*g)/(58.44*g*mol^-1))/(500xx10^-3*kg)=2.40*mol*kg^-1`

As always boiling point elevation depends on the number of discete particles in solution, and the salt solution gots more particles...