Where Did I Go Wrong in Calculating Hydroxide Ion Concentration?

[harambe]

Homework Statement

The hydroxide ion concentration in an aques H2CO3 solution is 4X10^{-4}M at 25°C OH- ion concentration in the solution is

Homework Equations

Ph=log(H+ or OH-) [/B]

The Attempt at a Solution

I calculated the PH of H+ in the solution which came to be 4.3979.Considering this to be water solution , I get POH to be 10.602..This doesn't match answer. Where did I go wrong[/B]

 

[Borek]

which came to be 4.3979

Check your math.

Note: you are showing way too many figures in your results. 4.4 would do here (and would be exactly as wrong as what you wrote).

 

[epenguin]

Don't forget to tell us what the question is. Given the concentration of hydroxide ion calculate the OH^- concentration is the easiest question I've seen here yet.

 

[Chestermiller]

Don't forget to tell us what the question is. Given the concentration of hydroxide ion calculate the OH^- concentration is the easiest question I've seen here yet.

Who is the George Washington bridge named after?

 

[epenguin]

Who is the George Washington bridge named after?

GW?