Question

what polyatomic ions have a 2 - charge?
check all that apply.
carbonate
phosphate
hydroxide
chromate
sulfite
hydrogen carbonate

Explanation:

To determine which polyatomic ions have a 2- charge, we recall the formulas and charges of each ion:

• Carbonate: $\ce{CO_3^{2-}}$ (charge is 2-).
• Phosphate: $\ce{PO_4^{3-}}$ (charge is 3-).
• Hydroxide: $\ce{OH^-}$ (charge is 1-).
• Chromate: $\ce{CrO_4^{2-}}$ (charge is 2-).
• Sulfite: $\ce{SO_3^{2-}}$ (charge is 2-).
• Hydrogen carbonate: $\ce{HCO_3^-}$ (charge is 1-).

So the ions with a 2- charge are carbonate, chromate, and sulfite.

Answer:

A. carbonate, D. chromate, E. sulfite