Respuesta :
Answer: The boiling point elevation of salt water solution is 0.55°C
Explanation:
To calculate the mass of water, we use the equation:
[tex]\text{Density of substance}=\frac{\text{Mass of substance}}{\text{Volume of substance}}[/tex]
Density of water = 1 g/mL
Volume of water = 122 mL
Putting values in above equation, we get:
[tex]1g/mL=\frac{\text{Mass of water}}{122mL}\\\\\text{Mass of water}=(1g/mL\times 122mL)=122g[/tex]
To calculate the elevation in boiling point, we use the equation:
[tex]\Delta T_b=iK_bm[/tex]
Or,
[tex]\Delta T_b=i\times K_b\times \frac{m_{solute}\times 1000}{M_{solute}\times W_{solvent}\text{ (in grams)}}[/tex]
where,
[tex]\Delta T_b[/tex] = ?
i = Vant hoff factor = 2 (For NaCl)
[tex]K_b[/tex] = molal boiling point elevation constant = 0.52°C/m.g
[tex]m_{solute}[/tex] = Given mass of solute (NaCl) = 3.80 g
[tex]M_{solute}[/tex] = Molar mass of solute (NaCl) = 58.55 g/mol
[tex]W_{solvent}[/tex] = Mass of solvent (water) = 122 g
Putting values in above equation, we get:
[tex]\Delta T_b=2\times 0.52^oC/m\times \frac{3.80\times 1000}{58.55g/mol\times 122}\\\\\Delta T_b=0.55^oC[/tex]
Hence, the boiling point elevation of salt water solution is 0.55°C
