Q. $0.01$ moles of a weak acid $HA \left( K _{ a }=2.0 \times 10^{-6}\right)$ is dissolved in $1.0 L$ of $0.1 M HCl$ solution. The degree of dissociation of $HA$ is ________ $\times 10^{-5}$ (Round off to the Nearest Integer). [Neglect volume change on adding HA. Assume degree of dissociation $<<1]$
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