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Chemistry Forums for Students => Undergraduate General Chemistry Forum => Topic started by: CABAL on September 21, 2007, 11:44:01 AM

Title: NaHCO3 in water?
Post by: CABAL on September 21, 2007, 11:44:01 AM

Hey all!

If I put NaHCO3 in water, does make Na+ and HCO3- ions right away?

I'm asking because I read that plants uses the carbondioxide from the compound,
but how do they do this?

Thanks,

Nicholas

Title: Re: NaHCO3 in water?
Post by: DevaDevil on September 21, 2007, 12:29:28 PM

sodium bicarbonate (baking soda) is soluble in water, so it will be present in ionic form. (solubility ~7.8 g/100 ml water)

(Bi)Carbonate in acidic solution will be in equilibrium with carbon dioxide and water. HCO₃^- + H⁺ <--> H₂O + CO₂

As far as plants go, I'll let a biologist do the talking.

Title: Re: NaHCO3 in water?
Post by: CABAL on September 21, 2007, 02:23:31 PM

Edit: Oh, if I dissolve 10g of NaHCO3 in 1 Liter of water, what would the pH be?
(an estimate would be enough)..sorry to be so pushy!

Thanks!!

Just what I needed!

Nicholas

Title: Re: NaHCO3 in water?
Post by: enahs on September 21, 2007, 04:13:56 PM

An estimate would be:
A little less then 7.0, assuming pure water.

Title: Re: NaHCO3 in water?
Post by: CABAL on September 21, 2007, 05:18:58 PM

Thanks!! :)

Very nice!!

Title: Re: NaHCO3 in water?
Post by: Borek on September 21, 2007, 05:22:50 PM

Quote from: enahs on September 21, 2007, 04:13:56 PM

An estimate would be:
A little less then 7.0, assuming pure water.

Nope. Between 8.0 and 8.1. That's without taking

H₂CO₃ = CO₂ + H₂O

equilibrium into account, which could remove some CO₂ from the solution, making it even more basic.