The tendency to form chains of identical atoms is known as ..............

Explanation

**Step-by-Step Solution:**

1. **Understanding the Concept of Chains**: The first step is to recognize what is meant by "chains of identical atoms." This refers to the bonding of atoms of the same element in a series, which creates a chain-like structure.

2. **Identifying the Element with Catenation**: The element that is most commonly associated with the ability to form chains of identical atoms is carbon. Carbon is unique in its ability to bond with itself and other elements.

3. **Explaining Catenation**: The term that describes the tendency of an element to form chains of identical atoms is called "catenation." This property allows carbon to form long chains and complex structures, leading to the vast diversity of organic compounds.

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