\(\Delta T_b = 0.18^o\) સે

\(\frac{{\Delta {T_b}}}{{\Delta {T_f}}} = \frac{{{K_b} \times m}}{{{K_f} \times m}}\)

\(\therefore \Delta {T_f} = \frac{{{K_b} \times \Delta {T_b}}}{{{K_b}}} = \frac{{0.18 \times 1.86}}{{0.512}}\)  \(\therefore \text{ }\Delta {{\text{T}}_{\text{f}}}\text{  =  0}\text{.65}{{\text{4}}^{o}}\) સે

ઠારબિંદુ  \(\text{ = 0  - }\Delta {{\text{T}}_{\text{f}}}\,\text{=}\,\text{0  - 0}\text{.654  = - 0}\text{.65}{{\text{4}}^{o}}\) સે