AB2 is 10% dissociated in water to A2+ and B$-$. The boiling point of a 10.0 molal aqueous solution of AB2 is __________$^\circ$C. (Round off to the Nearest Integer).
[Given : Molal elevation constant of water Kb = 0.5 K kg mol$-$1 boiling point of pure water = 100$^\circ$C]
Answer (integer)
106
Solution
AB<sub>2</sub> $\leftrightharpoons$ A<sup>+</sup> + 2B<sup>$-$</sup><br><br>$\therefore$ For AB<sub>2</sub>, n = 3<br><br>i = 1 + (n $-$ 1)$\alpha$<br><br>= 1 + (3 $-$ 1) $\times$ 0.1<br><br>= 1.2<br><br>Now, $\Delta$T<sub>b</sub> = K<sub>b</sub> (im)<br><br>$\Rightarrow$ T<sub>b</sub> $-$ T$_b^o$ = 1.2 $\times$ 0.5 $\times$ 10<br><br>$\Rightarrow$ T<sub>b</sub> $-$ 100 = 6<br><br>$\Rightarrow$ T<sub>b</sub> = 106
About this question
Subject: Chemistry · Chapter: States of Matter · Topic: Gas Laws
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