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Date: | Tue, 5 Feb 2002 16:15:32 -0500 |
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--On Tuesday, February 05, 2002 12:56 PM -0400 matesz
<[log in to unmask]> wrote:
> This is basic chemistry. Since both the sodium ion and the calcium ion
> are positively charged and basic, there is no way that calcium and sodium
> can form a chemical complex (positive ions repel one another).
>
> Since sodium can't bind with calcium, sodium can't be dragging calcium out
> of the body. The culprit must be something acidic and negatively charged
> and closely associated with sodium and consumed in large amounts that also
> has a high affinity for calcium.
Please explain to me how chloride ion is acidic and sodium ion is basic.
This is in direct contradiciton to what I learned in college general and
organic chemistry.
From what I remember there are two general ways to conceive of acid-base
chemistry. The first, and oldest, was coined by Bronsted-Lowry, who stated
that an acid is a substance that gives up hydrogen cation (H+) and a base
is a substance that can accept H+. Remember that what detrmines how acidic
a substance is is how much free H+ (or how many protons) it contains per
ml. The other way of conceiving acid-base chemistry was developed by Lewis.
Rather than seeing acid-base interactions simply in terms of exchanging
protons, he more generally states that an acid is a substance that can
accept electrons (or an electrophile), and a base is a substance that can
donate electrons (or a nucleophile). Under either of these systems,
chloride is cleary a base. It can accept a proton and it can donate it's
extra electron. Sodium, on the other hand is definitely a Lewis acid. It is
a positively charged, electron accpetor.
Peter Wendell
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