Here's how to determine which polyatomic ions have the same charge as the hydroxide ion (OH⁻):

* Hydroxide Ion (OH⁻): The hydroxide ion has a charge of -1.

Now, let's look at some common polyatomic ions and their charges:

* Nitrate (NO₃⁻): Charge of -1

* Carbonate (CO₃²⁻): Charge of -2

* Phosphate (PO₄³⁻): Charge of -3

* Ammonium (NH₄⁺): Charge of +1

* Sulfate (SO₄²⁻): Charge of -2

* Chlorate (ClO₃⁻): Charge of -1

Therefore, the following polyatomic ions have the same charge as the hydroxide ion:

* Nitrate (NO₃⁻)

* Chlorate (ClO₃⁻)