Calculate the H^(+) ion concentration in 0.05M formic acid at 298K. (K_(a)=1.8xx10^(-4) for HCOOH).

Calculate the H^(+) ion concentration in 0.05M formic acid at 298K. (K

1.	Calculate the H^(+) ion concentration in 0.05M formic acid at 298K. (K_(a)=1.8xx10^(-4) for HCOOH).
Answer» Solution :For a weak MONOBASIC acid, `[H_(3)O^(+)]=sqrt(CALPHA)` `[H_(3)O^(+)]=sqrt(0.04xx1.8xx10^(-4))=2.683xx10^(-3)"MOL "dm^(-3)` `[H_(3)O^(+)][OH^(-)]=10^(-14)` `therefore[OH^(-)]=(10^(-14))/(2.683xx10^(-3))=3.727xx10^(-12)"mol "dm^(-3)`