Plz help Solve this by using factor labeling

Consider the four elements above. which one of these elements will combine with oxygen in a 1: 1 ratio?

Predict the reactants of this chemical reaction. that is, fill in the left side of the chemical equation. be sure the equation you submit is balanced. (you can edit both sides of the equation to balance it, if you need to.) note: you are writing the molecular, and not the net ionic equation. > cacl2(aq) + h20(l)

Which substance can be broken down by chemical means