Question
Question: Name the product formed when Zn reacts with \(NaOH.\) A. \(Zn{(OH)_2}\) B. \(N{a_2}Zn{O_2}\) ...
Name the product formed when Zn reacts with NaOH.
A. Zn(OH)2
B. Na2ZnO2
C. H2
D. H2O
Solution
For solving this question, we know that metals that are placed above copper in the reactivity series react with dilute acids to form metal salts and hydrogen. So, the higher we move on the reactivity series, the more vigorous the metals will react
Complete step by step answer:
When metals react in a chemical reaction then it forms positive ions. For example, the dissociation of HCl in water forms H+ion. So, metals form basic oxide and hydroxides in reaction with acid.
Now, let’s move on to the question:
The question considers a chemical reaction when zinc reacts with excess sodium hydroxide it forms sodium zincate Na2ZnO2 and hydrogen gas. We know that zinc is a transition metal which shows moderate reactivity.
The chemical reaction that depicts that zinc reacts with NaOH to form sodium zincate with the evolution of hydrogen gas.
2NaOH(aq)+Zn(s)→Na2ZnO2(aq)+H2(g)
Also, we need to keep in mind that metals don’t react with strong bases. However, zinc acts as an exception to this property of metals. Also, we know that the element Zinc is atmospheric in nature and it can react with both acids and bases. So, it does react with Sodium hydroxide.
Thus, sodium zincate formed in the above reaction when a base reacts with a metal and a metal salt and hydrogen gas is formed as the products of the reaction.
∴The option C is correct answer.
Note:
We must know that the sodium zincate formed in the above reaction is referred to as an anionic zinc oxides or hydroxide. Also, remember that sodium zincate is a colorless compound but at the same time it is a good conductor of electricity in an aqueous solution. As in an aqueous solution, it releases ions that conduct electricity.