Respuesta :
Answer: The change in boiling point for 397.7 g of carbon disulfide (Kb = 2.34°C kg/mol) if 35.0 g of a nonvolatile, nonionizing compound is dissolved in it is [tex]2.9^0C[/tex]
Explanation:
Elevation in boiling point:
[tex]T_b-T^o_b=i\times k_b\times \frac{w_2\times 1000}{M_2\times w_1}[/tex]
where,
[tex]T_b[/tex] = boiling point of solution = ?
[tex]T^o_b[/tex] = boiling point of pure carbon disulfide= [tex]46.2^oC[/tex]
[tex]k_b[/tex] = boiling point constant =[tex]2.34^0Ckg/mol[/tex]
m = molality
i = Van't Hoff factor = 1 (for non-electrolyte)
[tex]w_2[/tex] = mass of solute = 35.0 g
[tex]w_1[/tex] = mass of solvent (carbon disulphide) = 397.7 g
[tex]M_2[/tex] = molar mass of solute = 70.0 g/mol
Now put all the given values in the above formula, we get:
[tex](T_b-46.2)^oC=1\times (2.34^oC/m)\times \frac{(35.0g)\times 1000}{70.0\times (397.7g)}[/tex]
[tex]T_b=49.1^0C[/tex]
Therefore, the change in boiling point is [tex](49.1-46.2)^oC=2.9^0C[/tex]
