A 6.50 molal solution of KOH (aq.) has a density of 1.89 g cm$-$3. The molarity of the solution is ____________ mol dm$-$3. (Round off to the Nearest Integer).
[Atomic masses : K : 39.0 u; O : 16.0 u; H : 1.0 u]
Answer (integer)
9
Solution
$m = {{1000 \times M} \over {1000 \times d - M \times {M_{solute}}}}$<br><br>$6.5 = {{1000 \times M} \over {1890 - M \times 56}}$<br><br>$\Rightarrow$ $12285 - 364M = 1000M$<br><br>$\Rightarrow$ $1364M = 12285$<br><br>$\Rightarrow$ $M = 9$
About this question
Subject: Chemistry · Chapter: Some Basic Concepts of Chemistry · Topic: Mole Concept
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