The K_a of monobasic acid A, B and C are 10^{ | vedclass

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(B) For a weak monobasic acid,$[H^+] = \sqrt{K_a 	imes C}$.For acid $A$: $[H^+]_A = \sqrt{10^{-6} 	imes 0.1} = \sqrt{10^{-7}} = 10^{-3.5}$. Thus,$pH

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$pOH (A) > pOH (B) > pOH (C)$

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(B) For a weak monobasic acid,$[H^+] = \sqrt{K_a 	imes C}$.For acid $A$: $[H^+]_A = \sqrt{10^{-6} 	imes 0.1} = \sqrt{10^{-7}} = 10^{-3.5}$. Thus,$pH(A) = 3.5$.For acid $B$: $[H^+]_B = \sqrt{10^{-8} 	imes 0.01} = \sqrt{10^{-10}} = 10^{-5}$. Thus,$pH(B) = 5$.For acid $C$: $[H^+]_C = \sqrt{10^{-10} 	imes 0.001} = \sqrt{10^{-13}} = 10^{-6.5}$. Thus,$pH(C) = 6.5$.Since $pH + pOH = 14$,we have $pOH = 14 - pH$.$pOH(A) = 14 - 3.5 = 10.5$.$pOH(B) = 14 - 5 = 9$.$pOH(C) = 14 - 6.5 = 7.5$.Comparing the values: $10.5 > 9 > 7.5$,which means $pOH(A) > pOH(B) > pOH(C)$.

The $K_a$ of monobasic acid $A, B$ and $C$ are $10^{-6}, 10^{-8}$ and $10^{-10}$ respectively. The concentrations of $A, B$ and $C$ are respectively $0.1 \ M, 0.01 \ M$ and $0.001 \ M$. Which of the following is correct for $pOH$ of $A, B$ and $C$?

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