Date: Fri, 29 Aug 97 10:57:22 cst From: mark.fisher@tpwd.state.tx.us To: cp@opus.hpl.hp.com Message-Id: <aabcdefg3292$foo@default> Subject: Re: Baking Soda, salt
>> ...i also would think that since base + acid = a salt... adding
>> baking soda to...any acidic planting medium would cause a
>> reaction leaving salt.
>It depends on what you mean be "salt". I guess I'm trying to say
>that the resulting "salt" from an organic reaction is different from
>the type of "salt" from an inorganic reaction. HCl (hydrochloric
>acid) mixed with NaOH (sodium hydroxide, a base) will result in NaCl
>(table salt) and H20 (water). Inorganic salts, or metallic salts,
>are definitely not good for CPs and this is why we use pure water
>for them.
>But baking soda and some organic acids would leave behind "salts"
>that are different than the inorganic variety, and I don't know how
>they would affect CPs.
>Any organic/inorganic chemists out there who will help us out?
As you already pointed out, an acid (H+) will react with a base (OH-)
to form water and a salt, composed of the anion from the acid and the
cation from the base.
Baking soda, NaHCO3, reacts with any acid to form water, CO2, and a
sodium salt of the acid, i.e.,
NaHCO3 + HR --> H20 + CO2 + NaR
where R can be any organic or inorganic anion. For example, if
vinegar (acetic acid) is used, the end product would be sodium
acetate, and hydrochloric acid would yield NaCl.
There are a variety of organic acids produced by the
decomposition/leaching of peat (humic and tannic acid, to name a few),
so the addition of baking soda would produce quite a mixture of sodium
salts. This would, of course, raise the pH of the soil, PLUS the
sodium would displace potassium, an important plant nutrient. This
would lower the fertility of the soil.
Many plants require an acid soil, as an acidic medium is necessary for
their roots to uptake nutrients. Many cp fall into this category.
High salt levels are typically not tolerated by plants, as their roots
cannot uptake water against the osmotic pressure. It doesn't matter
if the salt is inorganic or organic. This is why there are so few
marine vascular plants.
I suspect small amounts of baking soda could be tolerated by cp, but I
cannot imagine any benefits (unless the soil is TOO acid, and the
baking soda is simply raising the pH from, say, pH 2 to pH 5). Large
amounts of baking soda would likely be lethal.
Regards,
Mark
This archive was generated by hypermail 2b30 : Tue Jan 02 2001 - 17:31:09 PST