What are the properties and applications of carbonic acid?

Production and decomposition of carbonic acid

The production process of carbonic acid is not complicated. It also does not require too many ingredients or the use of advanced technologies. How is H₂CO₃, or carbonic acid, produced? The structural formula of this chemical indicates that it is formed through the dissolution of carbon dioxide (CO₂) in water (H₂O). The chemical obtained during this reaction shows several specific properties, which we will discuss below.

Properties of carbonic acid

What should you know about the physical and chemical properties of carbonic acid? This compound:

• is very weak and unstable,
• is odourless,
• is liquid,
• has a slightly acidic taste,
• exists only in diluted solutions,
• is readily degradable to water and carbon dioxide,
• colours methyl orange in red,
• co-creates the salts of carbonic acid (carbonates).

Dibasic acid H₂CO₃ forms two types of salts: acidic (bicarbonates) and neutral ones. Furthermore, carbonic acid cannot be produced in a concentrated form. Contemporary scientists have also found that carbonic acid can be obtained in gaseous form in trace amounts, although this is a very difficult task.

What is carbonic acid dissociation?

Carbonic acid in aqueous solutions is gradually decomposed. This phenomenon is called ionic dissociation. It is a two-step process which consists of gradual disconnection of hydrogen ions – first, one cation falls off, and then another. As a result of the dissociation, the entire chemical is broken down into 2 positive hydrogen ions and negative carbonate ions.

Occurrence and application of carbonic acid

Carbonic acid is distinguished by the fact that it occurs only in aqueous solutions. This property was used more than 200 years ago by the first soda makers who came up with the idea of passing carbon dioxide through water. CO₂ was obtained as a result of the reaction of acetic acid with sodium bicarbonate (baking soda). After saturating water with it, it was found that a carbonated beverage is much more refreshing than any other known soft drink.

Currently, the range of application of carbonic acid (H₂CO₃) in the carbonated beverages industry is very broad. It is safe to say that without this ingredient, we would never have known the taste of iconic beverages, such as classic soda water, carbonated mineral water or soft fizzy drinks such as orangeade, Coca-Cola, Pepsi or Sprite.

Carbonic acid also finds application in laboratories in the chemical industry, as well as in cosmetology – it is used to prepare advanced skin cleansing and rejuvenating treatments. In medicine, this compound is used, for example, by health resorts to prepare carbonic baths (recommended mainly for hypertensive patients and patients suffering from cardiovascular diseases).

How does carbonic acid affect the human body?

There are many myths surrounding carbonic acid. Some claim that the consumption of carbonic acid beverages contributes to the acidification and wasting of the stomach, whereas others believe that H₂CO₃ has no effect whatsoever on the human body. So, what is the truth, and who is right? Carbonated water or beverages usually have a slightly acidic taste, and although they can cause distressing symptoms, these are only relevant for those who struggle with gastrointestinal problems or indigestion. Of course, just like any other acidic food, H₂CO₃ consumed in excess can cause disruption to the acid–base balance in the body.