have been asked to write how i got this equation but i cant put it in words can you help me

Al2 Se3 +6 H2O ==> 2Al (OH)3 +3H2Se

i can do this but like i said putting it into words i just cannot make it coherant

The answer you should give is you found it on the internet. The reaction of aluminum selenide with water yeilds aluminum hydroxide and hydrogen selenide.

Sure, I'd be happy to help you explain the equation!

The given chemical equation represents a reaction between aluminum selenide (Al2 Se3) and water (H2O), which results in the formation of aluminum hydroxide (Al (OH)3) and hydrogen selenide (H2Se).

To understand how this equation is derived, we need to look at the valence of the elements involved and balance the equation based on the Law of Conservation of Mass.

First, let's examine the valence of each element:
- Aluminum (Al) has a valence of +3.
- Selenium (Se) has a valence of -2.
- Hydrogen (H) has a valence of +1.
- Oxygen (O) has a valence of -2.

Now let's analyze the equation step by step:

1. Aluminum selenide (Al2 Se3):
- Aluminum (Al) has a valence of +3, so we have 2 Al atoms with a total charge of +6.
- Selenium (Se) has a valence of -2, so we have 3 Se atoms with a total charge of -6.

2. Water (H2O):
- Hydrogen (H) has a valence of +1, so we have 6 H atoms with a total charge of +6.
- Oxygen (O) has a valence of -2, so we have 2 O atoms with a total charge of -4.

3. Aluminum hydroxide (Al (OH)3):
- Aluminum (Al) has a valence of +3, so we need 2 Al atoms to balance the charges.
- Oxygen (from water) (O) has a valence of -2, so we need 6 O atoms (three from each water molecule).
- Hydrogen (H) has a valence of +1, so we need 6 H atoms (two from each water molecule).

4. Hydrogen selenide (H2Se):
- Hydrogen (H) has a valence of +1, so we need 2 H atoms.
- Selenium (Se) has a valence of -2, so we need 1 Se atom.

To balance the equation, we need the same number of atoms on both sides:

Al2 Se3 + 6 H2O --> 2 Al (OH)3 + 3 H2Se

This equation shows that when 1 molecule of aluminum selenide reacts with 6 molecules of water, it produces 2 molecules of aluminum hydroxide and 3 molecules of hydrogen selenide.

Feel free to adjust or elaborate on this explanation, depending on the level of detail you require.