Question

what type of chemical reaction is 3Fe + 4H2O

Answer 1

Without the rest of the reaction it's more difficult, but not impossible to tell. You've got an element, (A), and a compound, (BC). They will react to "swap" some pieces

Do you know the 5 major types of reactions and what their general equations are?

Answer 2

I do know the 5 major types Synthesis (S) Decomposition (D) Single Replacement (SR) or Double Replacement (DR)

Answer 3

what is the general form for a single displacement?