What is the correct name for K_2SO_4?

• A. Potassium thiosulfate
• B. Potassium sulfate
• C. Potassium sulfite
• D. Potassium sulfur

Answer: (B)

Verified step by step guidance

1. Identify the ions present in the compound K_2SO_4. The formula consists of potassium ions (K^+) and the polyatomic ion sulfate (SO_4^{2-}).
2. Recall that potassium (K) is an alkali metal that forms a +1 charge ion (K^+). Since there are two potassium ions, the total positive charge is +2.
3. Recognize that the sulfate ion (SO_4^{2-}) carries a -2 charge, which balances the +2 charge from the two potassium ions, making the compound electrically neutral.
4. Understand the naming convention: when naming ionic compounds, the cation (positive ion) is named first, followed by the anion (negative ion). Here, the cation is potassium and the anion is sulfate.
5. Combine the names of the ions to form the correct name of the compound: 'Potassium sulfate'.