1.22 g of an organic acid is separately dissolved in 100 g of benzene (Kb = 2.6 K kg mol$-$1) and 100 g of acetone (Kb = 1.7 K kg mol$-$1). The acid is known to dimerize in benzene but remain as a monomer in acetone. The boiling point of the solution in acetone increases by 0.17$^\circ$C. The increase in boiling point of solution in benzene in $^\circ$C is x $\times$ 10$-$2. The value of x is ______________. (Nearest integer) [Atomic mass : C = 12.0, H = 1.0, O =16.0]
Answer (integer)
13
Solution
With benzene as solvent<br><br>$\Delta$T<sub>b</sub> = i K<sub>b</sub> m<br><br>$\Delta$T<sub>b</sub> = ${1 \over 2}$ $\times$ 2.6 $\times$ ${{1.22/{M_w}} \over {100/1000}}$ .... (1)<br><br>With Acetone as solvent<br><br>$\Delta$T<sub>b</sub> = i K<sub>b</sub> m<br><br>0.17 = 1 $\times$ 1.7 $\times$ ${{1.22/{M_w}} \over {100/1000}}$ ..... (2)<br><br>(1) / (2)<br><br>$${{\Delta {T_b}} \over {0.17}} = {{{1 \over 2} \times 2.6 + {{1.22/{M_w}} \over {100/1000}}} \over {1 \times 1.7 \times {{1.22/{M_w}} \over {100/1000}}}}$$<br><br>$\Delta$T<sub>b</sub> = ${{0.26} \over 2}$<br><br>$\Delta$T<sub>b</sub> = 13 $\times$ 10<sup>$-$2</sup><br><br>$\Rightarrow$ x = 13
About this question
Subject: Chemistry · Chapter: States of Matter · Topic: Gas Laws
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