The molecular formula of a commercial resin used for exchanging ions in water softening is C8H7SO3Na (mol. wt. = 206). The molecular formula of a commercial resin used for exchanging ions in water softening is C8H7SO3Na (mol.Oct 7, 2018

Commercial Resin for Water Softening
The molecular formula of a common commercial resin used for ion exchange in water softening is C8H7SO3Na. This resin is known as resin 8 or sodium polystyrene sulfonate.

Explanation:

Composition:
- The resin is composed of carbon (C), hydrogen (H), sulfur (S), oxygen (O), and sodium (Na) atoms.
- The molecular formula C8H7SO3Na indicates that there are 8 carbon atoms, 7 hydrogen atoms, 1 sulfur atom, 3 oxygen atoms, and 1 sodium atom in each molecule of the resin.

Ion Exchange Process:
- In water softening, the resin exchanges sodium ions (Na+) for calcium (Ca2+) and magnesium (Mg2+) ions, which are responsible for water hardness.
- The resin beads have negatively charged sites that attract and hold onto positively charged calcium and magnesium ions, releasing sodium ions in exchange.

Functionality:
- The resin acts as a water softener by removing hardness-causing minerals from water, thereby preventing scale buildup in pipes and appliances.
- It helps improve the efficiency of soap and detergents by allowing them to lather better in soft water.

Regeneration:
- Over time, the resin becomes saturated with calcium and magnesium ions and needs to be regenerated with a brine solution containing a high concentration of sodium chloride (salt).
- During regeneration, the resin releases the accumulated calcium and magnesium ions and takes up sodium ions from the brine solution, restoring its ion exchange capacity.
In conclusion, the molecular formula C8H7SO3Na represents the composition of a commercial resin used for ion exchange in water softening processes. This resin plays a crucial role in removing hardness-causing minerals from water, thereby improving its quality for various domestic and industrial purposes.