Al2(SO4)3 + Ca(OH)2 → Al(OH)3 + CaSO4

Hey there!

I assume you want this equation balanced.

Al₂(SO₄)₃ + Ca(OH)₂ → Al(OH)₃ + CaSO₄

Let's start by balancing the polyatomic ions, starting with SO₄.

There are 3 on the left and 1 on the right, so let's add a coefficient of 3 in front of the CaSO₄.

Al₂(SO₄)₃ + Ca(OH)₂ → Al(OH)₃ + 3CaSO₄

Now let's balance the polyatomic ion OH.

There are 2 on the left and 3 on the right, so let's put a coefficient of 3 in front of Ca(OH)₂ and a coefficient of 2 in front of Al(OH)₃.

Al₂(SO₄)₃ + 3Ca(OH)₂ → 2Al(OH)₃ + 3CaSO₄

Now let's balance Al.

There are 2 on the left and 2 on the right, so Al is already balanced.

Lastly, let's balance Ca.

There are 3 on the left and 3 on the right, so Ca is already balanced.

This means we're done! Here's the final balanced equation:

Al₂(SO₄)₃ + 3Ca(OH)₂ → 2Al(OH)₃ + 3CaSO₄  

Hope this helps!

since the atomic number is the number of protons in the nucleus, as we move to the left on the periodic table, the electrostatic pull between the nucleus and the valence electron shell decreases. as we move down a group (vertical column), the valence shell energy level gets further and further from the nucleus.