When 2 mL of sodium hydroxide solution is added to few pieces of granulated zinc in a test tube and then warm…

Question

When 2 mL of sodium hydroxide solution is added to few pieces of granulated zinc in a test tube and then warmed, the reaction that occurs can be written in the form of a balanced chemical equation as :

Accepted Answer

## Model Answer **(b) 2NaOH + Zn → Na₂ZnO₂ + H₂** This is the correctly balanced equation, with sodium zincate and hydrogen gas as products. Source: Chapter 2, Section 2.1.2 (Activity 2.4) ## Explanation The textbook (Activity 2.4) explicitly gives this equation: **2NaOH(aq) + Zn(s) → Na₂ZnO₂(s) + H₂(g)**. Check balance: Na=2, O=2, H=2+2=4 on LHS; Na=2, Zn=1, O=2, H=2 on RHS — all atoms balance. Option (b) is the only choice that is both correctly balanced and has the right products (Na₂ZnO₂ + H₂).

Science — CBSE Class 10 board question