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DMOC
Oct25-09, 12:27 PM
1. The problem statement, all variables and given/known data

A chemist filled a burette with a solution of sulfuric acid. She then titrated it into a solution of barium hydroxide to a point where there was excess acid. If a conductivity set-up is placed in the beaker with the barium hodroxide at the start of the reaction, what will happen?


2. Relevant equations

None


3. The attempt at a solution

This is a multiple choice question


a. Bulb glows continually
b. Bulb never glows
c. Bulb will nto glow until the acid is titrated
c. Bulb will glow then stop
e. The blub will glow, stop, then glow again.

The answer is e but I am unsure why it has the glow, stop, and then glow again effect.

chemisttree
Oct28-09, 02:19 PM
You are looking for dissociated species in solution. At first you have barium hydroxide then you have barium sulfate at equivalence. What happens when you add the next drop of ACID?

DMOC
Oct28-09, 06:04 PM
Oh, this question is old, but I was able to get the answer. It's E because with more acid, that neutralizes the solution which means no conductivity. Then with more acid, it's unbalanced, and will conduct again.

Hm ... looking back at this, can you explain why the solution is neutral if there is even amounts of acid and base substances?

chemisttree
Oct29-09, 04:23 PM
Barium sulfate precipitates leaving an equal amount of H+ and OH-... water.