In a solution containing `1.0xx10^(-3)M` acetic acid at `25^(@)C. K_(a)` of acetic acid is `1.80xx10^(-5)`. Select the correct statements.

Options

A. `[H^(+)]=1.34xx10^(-4)`
B. `[CH_(3)COO^(-)]=1.34xx10^(-4)`
C. `[CH_(3)COOH]= 8.66xx10^(-4)`
D. `[H^(+)]=1.35xx10^(-6)`

Answer

A, B

Explanation

`CH_(3)COOH hArrCH_(3)COO^(-)+H^(+)`
`[H^(+)]=sqrt(K_(a)xxC)`
`=sqrt(1.80xx10^(-5)xx1.0xx10^(-3))`
`=1.34xx10^(-4)`
Also, `K_(a)= ([CH_(3)COO^(-)][H^(+)])/([CH_(3)COOH])`
`1.8xx10^(-5) = ([CH_(3)COO^(-)][1.34xx10^(-4)])/(1.0xx10^(-3))`
`[CH_(3)COO^(-)]= 1.34xx10^(-4)`