Covalent compounds may exhibit ......... isomerism because covalent bonds are ......... and .......

Explanation

**Step-by-Step Solution:**

1. **Understanding Isomerism**:
- Isomerism refers to the phenomenon where compounds with the same molecular formula have different structural arrangements or spatial orientations. There are two main types of isomerism: structural isomerism and stereoisomerism.

2. **Types of Isomerism**:
- **Structural Isomerism**: This occurs when compounds have the same molecular formula but different structural formulas. Both covalent and ionic compounds can exhibit structural isomerism.
- **Stereoisomerism**: This occurs when compounds have the same molecular formula and structural formula but differ in the spatial arrangement of atoms.
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