The compound with the formula Cu₂SO₃ is called Copper(I) sulfite. Here's why:

* Cu₂: This indicates the presence of copper ions with a +1 charge each (Cu⁺). This is known as copper(I).

* SO₃: This is the sulfite ion, which has a -2 charge (SO₃²⁻).

To balance the charges, you need two copper(I) ions (2 x +1 = +2) to combine with one sulfite ion (-2).