How do you determine if a polyatomic ion needs to be counted together?

Calculate from Oxidation Number

The oxidation number of oxygen is -2, and the oxidation number of hydrogen is +1. Add together the oxidation numbers of all the atoms in the polyatomic ion. In the example, -2 +1 = -1. This is the charge on the polyatomic ion.

why is arctic sea ice important? arctic sea ice keeps the polar regions cool and moderate global climate. sea ice has a bright surface; 80 percent of the sunlight that strikes it is reflected back into space. as sea ice melts in the summer, it exposes the dark ocean surface.

i think slash and