What type of reaction is most likely to occur when barium reacts with fluorine? write the chemical equation for the reaction?

Answer is: this is synthesis reaction. 
Chemical reaction: Ba + F₂ → BaF₂.
Synthesis reaction is a type of reaction in which multiple reactants combine to form a single product.
In barium fluoride, barium has oxidation number +2 and fluorine has oxidation number -1, so compound has neutral charge.

The answer is 65.3312