ph question

[KARTOFIEL]

Hi

 

If a pond of 2000 gallon of liquid had a ph of 10.6 .Approximately how much volume og sulfuric acid will get the ph down to 9. I have no other information regarding the pond.

all help is greatly appreciated.

 

Karthik

[hermanntrude]

You'll need to know the concentration of the sulphuric acid to be able to answer this.

 

You'll also need to know what type of gallon. Gallons are different around the world.

[John Cuthber]

I can make a reasonable guess about the concentration of the acid and the number of litres in a gallon. What I can't do is estimate the buffering capacity of the pond.

There is't enough information to answer the question.

 

The best advice I can give is to take 2 gallons of water out of the pond. Take some of the acid and dilute it 1000 fold with water then titrate the bucket of water with the dilute acid.

However much dilute acid it takes to bring the pH of the 2 gallons up to pH 9 should be the same as the volume of undiluted acid it would take to drop the pH of the whole pond to pH9.

However this probaly won't work.

The strongly alkaline water suggests to me that there is something in it, perhaps limestone, keeping it alkaline (is it a newly made cement/ concrete lined pond?)

Until you add enough acid to react with all the alkaline stuff you are not going to make much difference to the pH.

[hermanntrude]

I can make a reasonable guess about the concentration of the acid and the number of litres in a gallon. What I can't do is estimate the buffering capacity of the pond.

There is't enough information to answer the question.

 

The best advice I can give is to take 2 gallons of water out of the pond. Take some of the acid and dilute it 1000 fold with water then titrate the bucket of water with the dilute acid.

However much dilute acid it takes to bring the pH of the 2 gallons up to pH 9 should be the same as the volume of undiluted acid it would take to drop the pH of the whole pond to pH9.

However this probaly won't work.

The strongly alkaline water suggests to me that there is something in it, perhaps limestone, keeping it alkaline (is it a newly made cement/ concrete lined pond?)

Until you add enough acid to react with all the alkaline stuff you are not going to make much difference to the pH.

 

I think this is a basic-level question, in a course prior to the introduction of buffers. I think it's safe to assume there is no buffer and the high pH is due to the presence of a strong base.