Which of the following ions has a positive charge?

• A. O^{2-}
• B. SO_4^{2-}
• C. Na^+
• D. Cl^-

Answer: (C)

Verified step by step guidance

1. Identify the charge on each ion by looking at the superscript notation: the superscript indicates the charge, where a positive sign (+) means a positive charge and a negative sign (-) means a negative charge.
2. For the ion \(O^{2-}\), the superscript '2-' indicates it has a charge of -2, meaning it is negatively charged.
3. For the ion \(SO_4^{2-}\), the superscript '2-' indicates it has a charge of -2, so it is also negatively charged.
4. For the ion \(Na^+\), the superscript '+' indicates it has a charge of +1, meaning it is positively charged.
5. For the ion \(Cl^-\), the superscript '-' indicates it has a charge of -1, so it is negatively charged.