What is the correct name for the ionic compound formed from K^+ and CrO_4^{2-} ions?

• A. Potassium chromite
• B. Potassium chromate
• C. Potassium chromium oxide
• D. Potassium dichromate

Answer: (B)

Verified step by step guidance

1. Identify the cation and anion involved in the compound. Here, the cation is K^+ (potassium ion) and the anion is CrO_4^{2-} (chromate ion).
2. Determine the charges of the ions: potassium ion has a charge of +1, and chromate ion has a charge of -2.
3. Balance the total positive and negative charges to form a neutral compound. Since potassium has a +1 charge and chromate has a -2 charge, two potassium ions are needed to balance one chromate ion.
4. Write the formula of the compound by combining the ions in the ratio that balances the charges: K_2CrO_4.
5. Name the compound by naming the cation first (potassium) followed by the name of the anion (chromate), resulting in the name 'potassium chromate'.