What is the correct formula for zinc nitrite?

To determine the correct formula for zinc nitrite, it is essential to understand the charges and composition of the involved species. Zinc typically exists as a cation with a +2 charge, represented as Zn²⁺. Nitrite, on the other hand, is a polyatomic ion with the formula NO2⁻, carrying a -1 charge.

To combine these ions correctly, we need to balance the charges. Since zinc has a +2 charge, two nitrite ions, each with a -1 charge, are required to neutralize the positive charge of zinc. This leads us to the formula Zn(NO2)2.

This formula indicates that there is one zinc ion and two nitrite ions, which collectively balance the overall charge. Other options, such as simply Zn(NO2) or Zn2(NO2)3, do not maintain this charge balance, while ZnN2O4 suggests a different combination of elements that does not represent zinc nitrite accurately. Thus, Zn(NO2)2 is the correct formula for zinc nitrite.