Respuesta :
Answer : The formula of a sulfur molecule in carbon disulfide is, [tex]S_8[/tex]
Explanation :
Formula used for Elevation in boiling point :
[tex]\Delta T_b=i\times k_b\times m[/tex]
or,
[tex]\Delta T_b=i\times k_b\times \frac{w_2\times 1000}{M_2\times w_1}[/tex]
where,
[tex]\Delta T_b[/tex] = boiling point of elevation = [tex]0.107^oC[/tex]
[tex]k_b[/tex] = boiling point constant of carbon disulfide = [tex]2.43^oC/m[/tex]
m = molality
i = Van't Hoff factor = 1 (for non-electrolyte
[tex]w_2[/tex] = mass of solute (sulfur sample) = 0.210 g
[tex]w_1[/tex] = mass of solvent (carbon disulfide) = 17.8 g
[tex]M_2[/tex] = molar mass of solute (sulfur sample) = ?
Now put all the given values in the above formula, we get:
[tex]0.107^oC=1\times (2.43^oC/m)\times \frac{(0.210g)\times 1000}{M_2\times (17.8g)}[/tex]
[tex]M_2=267.93g/mol[/tex]
The molar mass of sulfur sample is, 267.93 g/mol
Now we have to determine the formula of a sulfur molecule in carbon disulfide.
Let the compound of sulfur be, [tex]S_n[/tex]
Molar mass of [tex]S_n[/tex] = n × Molar mass of S
267.93 g/mol = n × 32 g/mol
n = 8
Thus, the formula of a sulfur molecule in carbon disulfide is, [tex]S_8[/tex]
