Question

Осуществите превращения: AlCl3 - Al(OH)3 - Al2 O3 - Al - Na[Al(OH)4]Приведите уравнения возможных реакций. Укажите условия их протекания

Answer 1

1) AlCl3 + 3 NaOH ---> Al(OH)3 (осадок) + 3 NaCl
                 t
2) 2 Al(OH)3 ---> Al2O3 + 3 H2O
        950'C, Na3[AlF6]
3) 2 Al2O3 ---> 4 Al + 3 O2 (газ)
              эл. ток
                                      р-р
4) 2 Al + 2 NaOH + 6 H2O ---> 2 Na[Al(OH)4] + 3 H2 (газ)

Answer 2

Chemical Transformations of Aluminum Compounds

To understand the chemical transformations of aluminum compounds, let's examine the reactions and conditions for the conversion of AlCl3 to Al(OH)3, Al2O3, Al, and Na[Al(OH)4].

1. Conversion of AlCl3 to Al(OH)3:

The reaction for the conversion of AlCl3 to Al(OH)3 involves the addition of water:

AlCl3 + 3H2O → Al(OH)3 + 3HCl.

This reaction occurs under standard conditions.

2. Conversion of Al(OH)3 to Al2O3:

The conversion of Al(OH)3 to Al2O3 involves dehydration, which can be achieved through heating:

2Al(OH)3 → Al2O3 + 3H2O [[5]](https://www.lib.tpu.ru/fulltext/m/2009/m11.pdf).

This reaction occurs at high temperatures, typically above 300°C.

3. Conversion of Al2O3 to Al:

The reduction of Al2O3 to Al can be achieved through the Hall-Héroult process, which involves the electrolysis of Al2O3 dissolved in molten cryolite (Na3AlF6):

2Al2O3 + 3C → 4Al + 3CO2.

This reaction occurs at high temperatures in the range of 950-1000°C.

4. Conversion of Al to Na[Al(OH)4]:

The reaction of Al with NaOH results in the formation of sodium tetrahydroxoaluminate:

2Al + 2NaOH + 6H2O → 2Na[Al(OH)4] + 3H2.

This reaction occurs under standard conditions.

In summary, the transformations of aluminum compounds involve various chemical reactions under specific conditions, including the addition of water, dehydration, reduction through electrolysis, and reaction with sodium hydroxide.

I hope this helps! If you have further questions, feel free to ask.