Click the answer you think is correct.

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For another question, select one of the options from the top of the menu on the left.

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You have the incorrect symbol for one of the elements.

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The Roman numeral indicates the charge per appearance of the positive ion.

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You did not correctly indicate the number of times the first element appears.

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Congratulations! You have selected the correct answer.

For another question, select one of the options from the top of the menu on the left.

Your choice indicates a polyatomic ion. However, this compound doesn't contain a negatively charged polyatomic ion.

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