Why are Na2CO3 sodium carbonate and NaHCO3 sodium bicarbonate alkaline?

The ionization equation for Na2CO3 (sodium carbonate) and NaHCO3 (sodium bicarbonate) when dissolved in water is.

na2co3=2na+ +co32-

nahco3=na+ +hco3-

Then there is hydrolysis: CO32- +H2O= reversible=HCO3- +OH-HCO3- +H2O=reversible=H2CO3+OH- and HCO3- also presents ionization of HCO3-= reversible=H+ +CO32-.

Because the degree of hydrolysis of HCO3- is greater than the degree of ionization, the aqueous solution of NaHCO3 is alkaline.

Na2CO3 is also basic according to the hydrolysis equation.

The hydrolysis of these two salts is alkaline, which promotes the ionization of water, so that the hydrogen and oxygen root ions of the solution increase, and the solution is alkaline.

HCO3- +H2O = (reversible) H2CO3 + OH-

CO32- +H2O = (reversible) HCO3- +OH-

Because they are all strong bases and weak salts.

Carbonate hydrolysis takes away the hydrogen ions of the water, and the hydroxide group increases, so it is alkaline.

The same goes for bicarbonate.

I guess you haven't reached high school yet, or you haven't learned this yet, and when you do, you'll understand hydrolysis and ionization equilibrium. They already say it in detail.

The chemical formula of sodium bicarbonate is NaHCO3, not NAH2CO3. This cracks because only one hydrogen ion (H+) in the sodium bicarbonate molecule is detached and binds to the carbonate ion (CO32-) instead of two hydrogen ions. Therefore, it only needs one brigade in its chemical formula, instead of two.

Answer: The reason why the aqueous solution of NaHCO3 is alkaline is due to the hydrolysis of HCO3- ions. First of all, NaHCO3 is ionized in water (NaHCO3=Na+ HCO3-), secondly, bicarbonate ions are combined with hydrogen ions ionized by water to undergo hydrolysis reaction, (HCO3- +H2O=H2CO3 +OH-), the middle = is a reversible sign], this process makes a part of hydroxide ions in the solution, so that the concentration of hydroxide ions in the water is greater than the concentration of hydrogen ions, so the solution is alkaline.

NaHCO3 is hydrolyzed and ionized in the solution, the degree of hydrolysis is greater than the degree of ionization, the solution is alkaline, and the hydrolysis equation is: HCO3-+H2O?H2CO3+OH-,NaHCO3 solution is alkaline, and the degree of hydrolysis is greater than the degree of ionization, C(OH-) C(H+), so the ion concentration relationship is:

c（na+）＞c（hco3-）＞c（oh-）＞c（h+）＞c（co32-）；

So the answer is: C(Na+) C(HCO3-) C(OH-) C(H+) C(CO32-).

Sodium bicarbonate (sodium bicarbonate), commonly known as baking soda. White fine crystals, less soluble in water than sodium carbonate. It is an industrial chemical with low toxicity.

Solids above 50 begin to gradually decompose to produce sodium carbonate, carbon dioxide and water, and completely decompose at 440. Sodium bicarbonate is an acid salt formed after neutralization of strong alkali and weak acid, which is weakly alkaline when dissolved in water. This property allows it to be used as a leavening agent in the production of edible molded items.

Sodium bicarbonate will remain sodium carbonate after the action is rounded, and too much use will make the finished product have an alkaline taste.

Categories: Education, Science, >> Learning Aid.

Analysis: Sodium carbonate, chemical formula: Na2CO3, common name "Su Min Ming Zhaoda", "soda ash" (it is worth noting that sodium carbonate is not an alkali, but a salt, and its aqueous solution is alkaline).

Under normal conditions, it is a white powder and a strong electrolyte. The density is 851, the melting point is 851, it is soluble in water, and it has the universal property of salt.

Production method: It is made of ammonia, carbon dioxide and saturated salt water. It is also made by combining alkali production method and artificial processing with natural alkali. It is an important raw material for bridge leasing in the chemical and industrial industries.

<>1. Sodium bicarbonate (sodium bicarbonate), with the molecular formula NaHCO3, is an inorganic salt, white crystalline powder, odorless, alkaline, soluble in water. It decomposes slowly in moist or hot air to produce carbon dioxide, which is heated to 270 degrees Celsius and completely decomposed. In case of acid, it decomposes strongly to produce carbon dioxide.

2. Sodium ions are the normal needs of the human body and are generally considered to be non-toxic. However, excessive intake may cause alkalosis, damage the liver, and induce high blood pressure.

3. Sodium bicarbonate solids begin to gradually decompose above 50 to generate sodium carbonate type brightness, water and carbon dioxide gas, which is often used as a leavening agent for making biscuits, pastries, steamed bread and bread. Sodium bicarbonate will remain sodium carbonate after action, and too much use will make the finished product have an alkaline taste.