Question

the reaction of coke with steam to give water is an example of what reaction

Answer 1

C+O2 ---------> CO2

2Na + 2H2O -------->2NaOH + H2

Answer 2

example of displacement reaction

C+H20=CO+H2
here the coke displaces hydrogen from water or hydrogen hydroxide.

NOTE: displacement reaction can only occur when an element of high reactivity displaces an element of low reactivity