Penurunan Titik Beku

(A)   Molalitas larutan glukosa

\begin{equation*}
\begin{split}
m_\text{glukosa} & = \frac{n_\text{glukosa}}{\text{massa}_{\text{ zat pelarut}} \text{ (kg)}}  \\\\
m_\text{glukosa} & = \frac{\dfrac{45}{180}}{0,25}  \\\\
m_\text{glukosa} & = 1 \text{ molal}
\end{split}
\end{equation*}

(B)   Penurunan titik beku larutan

\begin{equation*}
\begin{split}
\Delta T_f & = m \:.\: K_f  \\\\
\Delta T_f & = 1 \:.\: 1,86  \\\\
\Delta T_f & = 1,86^o \text{C}
\end{split}
\end{equation*}

(C)   Titik beku larutan

\begin{equation*}
\begin{split}
T_{\text{f larutan}} & = 0 - 1,86   \\\\
T_{\text{f larutan}} & = -1,86^o \text{C}
\end{split}
\end{equation*}