At $25^\circ\mathrm C$, $[\mathrm{OH^-}]=10^{{\rm pH}-14}\,\mathrm{mol\,dm^{-3}}$ in the usual dilute-solution <thermodynamic activity> approximation. Therefore \b[A: $10^{-2}\,\mathrm M$; B: $10^{-4}\,\mathrm M$; C: $10^{-4}\,\mathrm M$]. These are initial <concentrations>; only C is actively buffered at its stated value.

Solution

Past exam of the chemistry course of the year 1 of the natural sciences course of the University of Cambridge / 2021 / Paper 1 / 5 / b / i / Solution

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