In: Chemistry
a solution is initially 0.0884 M in an acid which is 21.4% ionized at equilibrium. Calculate the Ka for the solution at 25C (assume all acids are monoprotic)
Let the given monoprotic acid be represented by HX.
HXH+ +X- [equilibrium]
ICE table
[HX] [H+] [X-]
initial 0.0884M 0 0
change -0.0884*0.25=-0.0221M +0.0221M +0.0221M
equilibrium 0.0884-0.0221=0.0663M 0.0221M 0.0221M
ka=equilibrium constant=[H+][X-]/[HX]=(0.0221M)(0.0221M)/(0.0663M)=0.00737M
ka=0.00737M