I really don't mean to step on any toes, really I don't, but...
Quote:
|
Soda water does not contain any carbonic acid.
|
Actually it does. Water(H2O) plus Carbon Dioxide(CO2) equals H2CO3 equals Carbonic Acid. However not all of the Cabon Dioxide molecules in soda water combine with all of the water molecules so you still have some water, some carbon dioxide and a small amount of carbonic acid in soda water. The bad news is that there are usually lots of added salts (sodium chloride) in soda water to improve the taste and you would not want to add that much undesirable salt (not all salts are undesirable. Gypsum is a salt) to the soil to get enough carbonic acid to do the job. You would be creating more of a problem than a solution.
Quote:
|
Straight gypsum is alkaline.
|
If it is indeed gypsum it should not be alkaline it should be neutral. Gypsum works in a similar fashion as baking powder. Baking powder has three main components:
Sodium bicarbonate = alkaline (also known as
a base)
Dry cream of tartar = acidic
A filler, usually corn starch
The mixture is inactive when dry but when you mix in water the dry acid and dry base go into solution and start reacting to produce carbon dioxide bubbles.
Gypsum (calcium sulfate) is also composed of both an acid and a base of equal strength so that it is utimately neutral and will not change soil pH. The calcium is a base and the sulfur is an acid. When gypsum gets wet it gets active.
Adding additional sulfuric acids to the soil can be benificial if your soil already has a high lime content though. In soil with a high free lime (calcium carbonate CaCO3) content, sulfuric acid coming into contact with the lime (calcium carbonate) will react producing water (H2O), carbon dioxide (CO2) and calcium sulfate (gypsum CaSO4). No increase in hydrogen ion concentration occurs in this reaction, consequently no change in soil pH occurs. In this case you are creating gypsum within the soil. If you do not have enough lime in the soil and add enough sulphur to overcome the buffering capacity of the available lime content then there will be a decrease in soil pH. But in soils with a very high free lime content you can just add sulphur (up to six tons per acre for each percentage point of free lime content) instead of adding gypsum.