Question

\[{\text{Zn}} + {{\text{H}}_2}{\text{O}}\left( {{\text{steam}}} \right) \to {\text{A}} + {\text{B}}\] In the equation, A and B are:
A.\[{\text{Zn}}\] and ${{\text{H}}_2}$
B.${\text{Zn}}{{\text{H}}_2}$ and ${{\text{O}}_2}$
C.${\text{Zn}}{{\text{O}}_2}$ and ${{\text{H}}_2}$
D.${\text{ZnO}}$ and ${{\text{H}}_2}$

Answer 1

Hint: Metals react with water to get converted to their respective oxides as well as liberate hydrogen gas. Hence, the metal gets oxidized and water gets reduced.

Complete step by step solution:
Most of the metals react with water under different conditions, either ice-cold water, or water at room temperature, or hot water or steam. This reaction between the metal and water is dependent upon the position of the metal in the electrochemical series. The higher the metal is in the series, the higher are its chances of getting oxidized and hence those metals react with even ice-cold water.
Zinc is not much reactive with cold or room temperature water but reacts with steam to form zinc oxide and liberate hydrogen gas.

Hence, the products are zinc oxide and liberate hydrogen gas and the correct answer is option D.

Note:
In the periodic table, as we move from top to bottom in the periodic table, the reaction ability of the metals with water get more and more vigorous. Hence among the alkali metals, the highest reactibility with water is shown by caesium, although it is radioactive. Zinc appears after the alkali and the alkaline earth metals in the electrochemical series and is hence much less reactive than them. This can also be attributed to the stable electronic confirmation of zinc which limits its reactivity. This is why different iron objects are coated or galvanized with zinc too.