What does alumina and soda ash produce by reaction?

Sorry ......I haven't learned to ask questions:

When I asked the teacher, she didn't know how tall she was: How tall are you? ：

Always review the guidance and practice of the Sujiao version.,It seems to be the chapter of aluminum.,The back answer is:

Poof......I'm the ...... of the Renjiao versionFollow-up:

Fe + 2H2SO4 = 2H2O + FeSO4 + SO4 Supplement:

Wrong, the one above is SO2, not SO4, it's already trimmed, you just need to change SO4 to SO2 and ask:

No, a small amount of iron, sulfuric acid is concentrated, it should show strong oxidation, it should be 3-valent iron

If it is 2-valent iron, it is ferrous sulfate and hydrogen, and it is not a displacement reaction? ：

No, you have to pay attention to the concentrated sulfuric acid asked:

It is a small amount of iron, and concentrated sulfuric acid is to produce 3-valent iron sulfate, and if there is too much iron, the remaining iron will react with 3-valent iron to form 2-valent ferrous iron. Or if you ask the teacher, I can't figure it out: I know and ask:

Alumina is amphoterical, where it is acidic, soda ash is alkaline, and reacts into sodium metaaluminate and CO2

Na2CO3 is a strong base and weak salt, and Al2O3 amphoteric oxide is acidic when exposed to alkali under heating conditions.

3na2co3+al2o3==2na3alo3+3co2↑al2o3+3h2o==2al(oh)3

The white gelatinous precipitate should be Al(OH)3 produced by the reaction of H2O and Al2O3

Alumina is a basic oxide, but it is also an acid oxide, alumina is a more typical amphoteric oxide, which can react with both acid and alkali to produce salt and water.

It can be soluble in inorganic acids and alkaline solutions, almost insoluble in water, or in non-polar organic solvents, and alumina is a stable oxide belonging to aluminum. It is called bauxite in the ceramic industry and mining industry and material science, which is relatively insoluble in water, and odorless and tasteless, with extremely hard texture and easy to absorb moisture but not deliquescent, and the burned does not absorb moisture. In addition to the announced scale of alumina, the total scale of alumina planned construction in the country is 10,000 tons, which is close to the total scale of all proposed alumina projects abroad.

Characteristic.

Alumina is a white solid that is also known as bauxite in mining, ceramics and materials science. The amount of alumina on the earth is only second only to silicon oxide, is one of the ceramic raw materials, in the oxide aluminum and oxygen have a strong bond, so that alumina has the highest hardness in the oxide, its chemical stability is high and has excellent corrosion resistance to most acidic, alkaline, salt and molten solutions.

There are many homogeneous crystals of alumina, and there are more than 10 kinds of known ones, and there are mainly 3 crystal forms, namely -Al2O3, -Al2O3, and -Al2O3. Among them, the structure is different and the properties are also different, and it is almost completely converted to -Al2O3 at high temperatures above 1300.

Aluminium can react with bases to form metaaluminate compounds.

Knowledge point analysis:

A common reaction is the reaction of aluminum with strongly basic sodium hydroxide (NaOH) or potassium hydroxide (KOH) to form metaaluminate ions.

The reaction equation is as follows:

2al + 2naoh + 6h2o 2na[al(oh)4] +3h2

In this reaction, aluminum reacts with hydroxides to form metaaluminate ions (Na[Al(OH)4]) and hydrogen is released at the same time.

Application of knowledge points:

1.Metaaluminate ions are widely used in the production process of Portland cement and glass in the chemical industry as thickeners, preservatives, etc.

2.Metaaluminate ions can also be used in wastewater treatment as a precipitant to remove heavy metal ions from wastewater.

Example Explanation:

Question: When 5g of aluminium is added to an excess sodium hydroxide solution, what is the number of moles of metaaluminate ions generated?

Answer: According to the reaction equation, it can be known that 2 mol of aluminum and 6 mol of sodium hydroxide react to form 2 mol metaaluminate ions.

First, calculate the number of moles of aluminum:

The relative atomic mass of aluminium is 27 g mol, so the molar number of 5 g of aluminium is:

5 g / 27 g/mol ≈ mol

Since sodium hydroxide is excessive, the molar ratio is 1:3, and the number of moles of metaaluminate ions is 1 2 mol of aluminum:

mol × 1/2) = mol

So, the number of moles of metaaluminate ions produced is about mol.

Soda ash reacts with aluminum hydroxide and does not produce aluminium oxide tremor, which refers to sodium hydroxide (NaOH), aluminum hydroxide (Al(OH)3), which is a weakly acidic salt. The reaction between them is actually an acid-base neutralization reaction, and the products are water and sodium aluminate (Naalo2). The equation for this reaction is as follows:

Al(OH)3 + NaOH Naalo2 + 2H2O From this reaction equation, it can be seen that there is no aluminum oxide (Al2O3) in the product. Of course, the sodium aluminate here may decompose at high temperatures to produce sodium hydroxide and aluminum oxide, but under normal acid-base reaction conditions, this decomposition does not occur.

Answer The essence of the reaction between aluminum and acid and alkali is: <

al3 ＋，2h ＋

H2 is nothing more than the ionization of H** in the base with water. The oxidizing agents are acid and water, respectively. The god of silver.

The elements that can react with hydroluvil alumina are active metal elements, such as sodium and potassium in alkali metals.

The chemical reaction equation is as follows:Sodium early peipei reacts with aluminum hydroxide:2na+2al(oh)₃=2naalo₂+h₂↑+2h₂o

Potassium reacts with aluminum hydroxide:2K+2Al(OH) =2kalo +H is missing +2HO

In fact, there is also a process, but the existence of aluminum hydroxide is very short.

Because alumina is an insoluble solid, when it reacts with a strong base, it becomes aluminum hydroxide, and aluminum hydroxide is an insoluble substance, which will cover the surface of alumina and prevent the reaction from being prepared, but aluminum hydroxide can be dissolved in a strong alkali, so it will be destroyed and reacted quickly, if alumina wants to be completely reacted, then aluminum hydroxide will not exist, so when alumina reacts with a strong alkali, metaaluminate ions are generated.

Soluble aluminum ions are different, even if the resulting aluminum hydroxide is dissolved, as long as the alkali is not excessive, then the metaaluminate ions will react with the aluminum ions and form aluminum hydroxide. Therefore, as long as the strong alkali is not overcovered, aluminum hydroxide will exist.