The products of the reaction \( \text{BeF}_2 + \text{Mg} \) are \( \text{MgF}_2 + \text{Be} \).
The balanced reaction is: \[ \text{BeF}_2 + \text{Mg} \rightarrow \text{MgF}_2 + \text{Be} \]
This represents a replacement reaction, specifically a single replacement reaction, where magnesium replaces beryllium in the beryllium fluoride compound.
So, the correct answers are:
- The products: \( \text{MgF}_2 + \text{Be} \)
- Type of reaction: replacement.