K2SO4?
The Correct Answer and Explanation is:
The correct name for K₂SO₄ is potassium sulfate.
Explanation:
K₂SO₄ is an example of an ionic compound made up of potassium ions and sulfate ions. Let us break down the formula to understand its correct name:
- K stands for potassium. Potassium is a metal that forms a +1 charged ion, written as K⁺.
- The subscript 2 next to potassium (K) indicates that two potassium ions are present to balance the charges.
- SO₄ is a polyatomic ion known as sulfate, which has a charge of -2.
In ionic compounds, the total positive and negative charges must balance. Since each potassium ion has a +1 charge and the sulfate ion has a -2 charge, it takes two potassium ions to balance the charge of one sulfate ion. The formula K₂SO₄ reflects this balance:
- Two K⁺ ions contribute a total charge of +2.
- One SO₄²⁻ ion contributes a charge of -2.
- The overall charge is neutral, which is expected for a stable ionic compound.
Naming conventions:
For ionic compounds:
- The name of the metal (cation) comes first. Here, it is potassium.
- The name of the polyatomic ion (anion) comes second. Here, it is sulfate.
Therefore, the correct name is potassium sulfate.
This compound is commonly used in agriculture as a fertilizer because it provides both potassium and sulfur, essential nutrients for plant growth. Unlike potassium chloride, potassium sulfate does not add chloride ions to the soil, making it a preferred choice for chloride-sensitive crops. It appears as a white crystalline solid and dissolves readily in water.
