Understanding the history of vitamin nomenclature can sometimes be confusing, as vitamins were often initially identified by letters and numbers before their chemical structures were fully understood and given specific names. This question asks about the previous name for Riboflavin.

Identifying the Previous Name of Riboflavin

Riboflavin is an important vitamin that is part of the B vitamin group. B vitamins are essential nutrients that play various crucial roles in the body, including energy metabolism.

When vitamins were first being discovered and categorized, they were often assigned numerical designations within their group. Riboflavin was one of the early B vitamins to be identified.

Historically, Riboflavin was known by a simpler name that indicated its place within the B complex group. This name was Vitamin B₂.

Let's look at the options provided:

• Vitamin B₁: This vitamin is known as Thiamine.
• Vitamin B₆: This vitamin is known as Pyridoxine.
• Vitamin B₁₂: This vitamin is known as Cobalamin.
• Vitamin B₂: This vitamin is known as Riboflavin.

Based on historical context and scientific classification, Riboflavin was originally referred to as Vitamin B₂ before the chemical name Riboflavin became widely adopted. Thus, the previous name for Riboflavin is Vitamin B₂.

Riboflavin is crucial for converting food into energy, supporting vision, and maintaining healthy skin and nerves. Knowing that Riboflavin is Vitamin B₂ helps in understanding older literature and discussions about vitamins.

Therefore, the vitamin previously called Vitamin B₂ is Riboflavin.