Respuesta :
Answer: The order of increasing boiling points follows:
[tex]\text{Ethanol }<Mg(NO_3)_2<\text{ NaCl}[/tex]
Explanation:
The expression of elevation in boiling point is given as:
[tex]\Delta T_b=i\times k_b\times m[/tex]
where,
[tex]\Delta T_b[/tex] = Elevation in boiling point
i = Van't Hoff factor
[tex]T_b[/tex] = change in boiling point
[tex]k_b[/tex] = boiling point constant
m = molality
For the given options:
- Option 1: 0.050 m [tex]Mg(NO_3)_2[/tex]
Value of i = 3
So, molal concentration will be = [tex](0.05)\times 3=0.15m[/tex]
- Option 2: 0.100 m ethanol
Value of i = 1 (for non-electrolytes)
So, molal concentration will be = [tex](0.100)\times 1=0.100m[/tex]
- Option 3: 0.090 m NaCl
Value of i = 2
So, molal concentration will be = [tex](0.09)\times 2=0.18m[/tex]
As, the molal concentration of NaCl is the highest, so its boiling point will be the highest.
Thus, the order of increasing boiling points follows:
[tex]\text{Ethanol }<Mg(NO_3)_2<\text{ NaCl}[/tex]
