Mention, name, instance, specify are comparable when they mean to make clear or specific by referring to something explicitly.
Mention indicates a calling attention to, usually by name where possible, sometimes by a brief, cursory, or incidental reference.
Name implies clear mention of a name and therefore may suggest greater explicitness.
Instance may indicate clear explicit reference or definite emphasis as a typical example or special case.
Specify implies statement so explicit, detailed, and specific that misunderstanding is impossible.