Final answer:
The linkage in popular synthetic fabrics that are condensation polymers is the amide linkage. Polyamides, like Nylon-66, occur through condensation reactions forming polymers used in clothing and household items.
Step-by-step explanation:
The linkage found in many popular synthetic fabrics that are condensation polymers is known as amide linkage. Condensation polymerization, also called step-growth polymerization, is a process where monomers with two or more functional groups react to form a small molecule like water as a byproduct, allowing the monomers to join together. Polyamides and polyesters are two common types of condensation polymers. Polyamides, such as Nylon-66, are widely used in fibers and clothing due to their strength and durability. Nylon, invented in 1935, continues to have a wide range of applications in various products from kitchenware to carpets.