What is the chemical formula for aluminum sulfate?
The correct answer and explanation is:
The chemical formula for aluminum sulfate is Al₂(SO₄)₃.
Explanation:
Aluminum sulfate is a chemical compound composed of aluminum, sulfur, and oxygen. It is formed when aluminum reacts with sulfuric acid. The chemical formula of aluminum sulfate can be broken down into its components:
- Aluminum (Al): The metal aluminum has a valence of +3, meaning it needs to form bonds with three negative ions to balance its positive charge.
- Sulfate (SO₄²⁻): The sulfate ion is a polyatomic ion with a charge of -2. Each sulfate ion consists of one sulfur atom bonded to four oxygen atoms.
For aluminum sulfate, two aluminum ions (each with a +3 charge) balance the charge of three sulfate ions (each with a -2 charge). Therefore, the formula is Al₂(SO₄)₃, meaning two aluminum ions combine with three sulfate ions.
In the solid form, aluminum sulfate is typically seen as a white crystalline substance. It is highly soluble in water, making it useful in several industrial applications. One common use is in water purification, where aluminum sulfate helps to coagulate impurities, making them easier to remove.
Aluminum sulfate is also employed in the manufacture of paper, where it is used as a sizing agent to control the absorbency of the paper. Furthermore, it is sometimes used in gardening to acidify soil, particularly in the case of plants that thrive in acidic conditions, like blueberries.
Understanding the composition of aluminum sulfate at the molecular level highlights its versatility and importance in industrial, agricultural, and environmental processes.